diff --git a/components/experimental/branch-switcher.jsx b/components/experimental/branch-switcher.jsx
index 2abd32e..7270ca9 100644
--- a/components/experimental/branch-switcher.jsx
+++ b/components/experimental/branch-switcher.jsx
@@ -46,7 +46,7 @@ function NewIndicator({ visible }) {
 
 /* ── Single branch row ─────────────────────────────────── */
 
-function BranchRow({ id, label, active, isNew, origin, onClick }) {
+function BranchRow({ id, label, active, isNew, isPaused, origin, onClick }) {
   const isActive = Boolean(active);
 
   return (
@@ -80,8 +80,18 @@ function BranchRow({ id, label, active, isNew, origin, onClick }) {
         )}
       </span>
 
-      {/* Passive new-result indicator (only for inactive branches) */}
-      {!isActive && <NewIndicator visible={isNew} />}
+      {/* Passive indicators: pause + new */}
+      <span className="flex items-center gap-1.5 flex-none">
+        {!isActive && isPaused && (
+          <span
+            className="text-[10px] text-gray-400"
+            title="Done for now"
+          >
+            Paused
+          </span>
+        )}
+        {!isActive && <NewIndicator visible={isNew} />}
+      </span>
     </button>
   );
 }
@@ -92,6 +102,7 @@ export default function ExperimentalBranchSwitcher({
   branches = [],
   activeBranchId,
   branchNewResults = {},
+  branchPauseState = [],
   onBranchSelect,
 }) {
   if (!branches.length) return null;
@@ -119,6 +130,7 @@ export default function ExperimentalBranchSwitcher({
             label={branch.label}
             active={activeBranchId === branch.id}
             isNew={Boolean(branchNewResults[branch.id])}
+            isPaused={branchPauseState.includes(branch.id)}
             origin={branch.origin}
             onClick={() => onBranchSelect?.(branch.id)}
           />
diff --git a/components/reasoning-workspace.jsx b/components/reasoning-workspace.jsx
index c7475ae..e829bc4 100644
--- a/components/reasoning-workspace.jsx
+++ b/components/reasoning-workspace.jsx
@@ -351,9 +351,14 @@ function BranchNotebookContent({
   openQuestions,
   lateResults,
   inactiveBranchNewResults,
+  doneForNowBranchIds,
+  onDoneForNow,
+  branchId,
 }) {
   const hasOpenItems = openQuestions && openQuestions.length > 0;
   const hasContributions = contributions && contributions.length > 0;
+  const isPaused = doneForNowBranchIds?.includes(branchId) || false;
+  const isBranchActive = !isPaused;
 
   return (
     <div className="space-y-6">
@@ -407,9 +412,35 @@ function BranchNotebookContent({
         <UpdatedConnectionCard update={lateResults[0]} />
       )}
 
-      {/* Quiet state — only when there are no open items and no updates */}
+      {/* Done for now control — only when branch is not already paused */}
+      {isBranchActive && onDoneForNow && contributions.length > 0 && (
+        <div className="flex justify-end pt-1">
+          <button
+            onClick={(e) => { e.stopPropagation(); onDoneForNow(); }}
+            style={{ cursor: "pointer" }}
+            className="rounded-lg border border-gray-300 bg-white px-4 py-2 text-sm font-medium text-gray-600 hover:bg-gray-50 transition whitespace-nowrap"
+          >
+            Done for now
+          </button>
+        </div>
+      )}
+
+      {/* Quiet state */}
       {!hasOpenItems && !lateResults?.length && (
-        <QuietStateCard />
+        <div className="rounded-lg border border-gray-200/60 bg-gray-50/40 px-5 py-5 text-center">
+          {isPaused ? (
+            <>
+              <p className="text-sm leading-relaxed text-gray-500 mb-1">
+                Nothing more to add here right now
+              </p>
+              <p className="text-xs leading-relaxed text-gray-400">
+                This branch is paused. Reasoning preserved — return when you have more information.
+              </p>
+            </>
+          ) : (
+            <QuietStateCard />
+          )}
+        </div>
       )}
     </div>
   );
@@ -805,6 +836,11 @@ export default function ReasoningWorkspace({
   branchLocalContributions,
   branchLocalLateResults,
   inactiveBranchNewResults,
+  activeBranchIdForNotebook,
+  // ── RTO.27B — provisional pause state ──
+  doneForNowBranchIds,
+  onDoneForNow,
+  onReopenBranch,
 }) {
   const [investigationHistory, setInvestigationHistory] = useState([]);
   const turnCounter = useRef(0);
@@ -1115,6 +1151,9 @@ export default function ReasoningWorkspace({
                     openQuestions={branchLocalQuestions || []}
                     lateResults={branchLocalLateResults || []}
                     inactiveBranchNewResults={inactiveBranchNewResults || {}}
+                    doneForNowBranchIds={doneForNowBranchIds || []}
+                    onDoneForNow={onDoneForNow}
+                    branchId={activeBranchIdForNotebook}
                   />
                 )}
 
@@ -1149,14 +1188,12 @@ export default function ReasoningWorkspace({
                     {genuineCompletion && (
                       <CompletionCard summary={resolveCurrentSummary(propUnderstanding || graph?.currentSummary || result?.updatedSituationGraph?.currentSummary)} />
                     )}
-                    {!genuineCompletion && (
-                      experimentalBranches && experimentalBranches.length > 0 ? (
-                        // In experiment mode: quiet facilitator state, not evidence limit verdict
-                        <QuietStateCard />
-                      ) : (
-                        <EvidenceLimitCard summary={resolveCurrentSummary(propUnderstanding || graph?.currentSummary || result?.updatedSituationGraph?.currentSummary)} />
-                      )
-                    )}
+                    {!genuineCompletion && experimentalBranches && experimentalBranches.length > 0 ? (
+                      // Quiet state is handled inside BranchNotebookContent for experiment mode
+                      null
+                    ) : !genuineCompletion ? (
+                      <EvidenceLimitCard summary={resolveCurrentSummary(propUnderstanding || graph?.currentSummary || result?.updatedSituationGraph?.currentSummary)} />
+                    ) : null}
                   </>
                 )}
 
diff --git a/components/scenario-form.jsx b/components/scenario-form.jsx
index 20e9980..d2f3864 100644
--- a/components/scenario-form.jsx
+++ b/components/scenario-form.jsx
@@ -229,6 +229,10 @@ export default function ScenarioForm() {
   // Pre-seed Competitor development with a late result for RTO.27A testing
   const [branchNewResults, setBranchNewResults] = useState({ "branch-a": true });
 
+  /* ── RTO.27B — provisional done-for-now state (experimental) ── */
+
+  const [doneForNowBranchIds, setDoneForNowBranchIds] = useState([]);
+
   /* ── RTO.26B — experimental branch-scoped reasoning fixture ───── */
 
   const branchScoped = useBranchScopedFixture();
@@ -270,15 +274,22 @@ export default function ScenarioForm() {
   }, [activeBranch, branchScoped]);
 
   // Determine which non-active branches have new results for passive indicator
+  // (RTO.27B: also include done-for-now branches so pause state is visible)
   const inactiveBranchNewResults = useMemo(() => {
     const result = {};
     BRANCHES.forEach(b => {
-      if (b.id !== activeBranchId && b.id in branchNewResults) {
-        result[b.id] = true;
+      if (b.id !== activeBranchId) {
+        if (b.id in branchNewResults) {
+          result[b.id] = true;
+        }
+        // Show pause indicator on any done-for-now branch
+        if (doneForNowBranchIds.includes(b.id)) {
+          result[b.id] = true;
+        }
       }
     });
     return result;
-  }, [activeBranchId, BRANCHES, branchNewResults]);
+  }, [activeBranchId, BRANCHES, branchNewResults, doneForNowBranchIds]);
 
   /* Restore persisted session on mount (Phase 3) ─────────── */
   useEffect(() => {
@@ -472,6 +483,17 @@ export default function ScenarioForm() {
                     branchLocalContributions={experimentalBranchContributions.length > 0 ? experimentalBranchContributions : undefined}
                     branchLocalLateResults={experimentalBranchLateResults.length > 0 ? experimentalBranchLateResults : undefined}
                     inactiveBranchNewResults={Object.keys(inactiveBranchNewResults).length > 0 ? inactiveBranchNewResults : undefined}
+                    activeBranchIdForNotebook={activeBranchId}
+                    doneForNowBranchIds={doneForNowBranchIds}
+                    onDoneForNow={() => {
+                      if (activeBranchId && !doneForNowBranchIds.includes(activeBranchId)) {
+                        setDoneForNowBranchIds(prev => [...prev, activeBranchId]);
+                      }
+                    }}
+                    onReopenBranch={(id) => {
+                      setDoneForNowBranchIds(prev => prev.filter(x => x !== id));
+                      setActiveBranchId(id);
+                    }}
                     onRestart={() => { setStatus("idle"); setResult(null); setScenario(""); }}
                   />
                 );
@@ -484,14 +506,30 @@ export default function ScenarioForm() {
                 branches={BRANCHES}
                 activeBranchId={activeBranchId}
                 branchNewResults={branchNewResults}
+                branchPauseState={doneForNowBranchIds}
                 onBranchSelect={(id) => {
-                  if (id !== activeBranchId) {
-                    setActiveBranchId(id);
+                  if (id === activeBranchId) return;
+                  // Reopen: if the selected branch is paused, clear its pause state
+                  if (doneForNowBranchIds.includes(id)) {
+                    setDoneForNowBranchIds(prev => prev.filter(x => x !== id));
                   }
+                  setActiveBranchId(id);
                 }}
               />
             </div>
           </div>
+          {/* ── RTO.27B — simulated late update for paused branch (experimental dev control) ─ */}
+          <div className="mt-2 flex items-center gap-3">
+            <button
+              onClick={() => {
+                // Simulate a late result arriving on the customer-demand branch while paused
+                setBranchNewResults(prev => ({ ...prev, "branch-b": true }));
+              }}
+              className="rounded border border-purple-200/60 bg-purple-50 px-3 py-1.5 text-xs text-purple-700 hover:bg-purple-100 transition"
+            >
+              Simulate late update on Customer demand
+            </button>
+          </div>
         </>
       )}
 
@@ -669,6 +707,17 @@ export default function ScenarioForm() {
                     branchLocalContributions={experimentalBranchContributions.length > 0 ? experimentalBranchContributions : undefined}
                     branchLocalLateResults={experimentalBranchLateResults.length > 0 ? experimentalBranchLateResults : undefined}
                     inactiveBranchNewResults={Object.keys(inactiveBranchNewResults).length > 0 ? inactiveBranchNewResults : undefined}
+                    activeBranchIdForNotebook={activeBranchId}
+                    doneForNowBranchIds={doneForNowBranchIds}
+                    onDoneForNow={() => {
+                      if (activeBranchId && !doneForNowBranchIds.includes(activeBranchId)) {
+                        setDoneForNowBranchIds(prev => [...prev, activeBranchId]);
+                      }
+                    }}
+                    onReopenBranch={(id) => {
+                      setDoneForNowBranchIds(prev => prev.filter(x => x !== id));
+                      setActiveBranchId(id);
+                    }}
                     onRestart={() => {
                   clearSession();
                   setStatus("idle");
@@ -691,11 +740,14 @@ export default function ScenarioForm() {
                 branches={BRANCHES}
                 activeBranchId={activeBranchId}
                 branchNewResults={branchNewResults}
+                branchPauseState={doneForNowBranchIds}
                 onBranchSelect={(id) => {
-                  /* User intentionally navigates — nothing more */
-                  if (id !== activeBranchId) {
-                    setActiveBranchId(id);
+                  if (id === activeBranchId) return;
+                  // Reopen: if the selected branch is paused, clear its pause state
+                  if (doneForNowBranchIds.includes(id)) {
+                    setDoneForNowBranchIds(prev => prev.filter(x => x !== id));
                   }
+                  setActiveBranchId(id);
                 }}
               />
             </div>