Restore safe Duke grants in early legacy games

docs/RULE_DECISIONS.md

@@ -1,10 +1,20 @@
 # Rule decision index
 
+## First-turn Duke proof and occupied Ecaz displacement — 29 October 2026
+
+**Prototyped / Partial.** Public first-turn pre-battle state can prove that an
+unstamped legacy game has no earlier capture; explicit uncertainty and ambiguous
+or later history remain guarded. The public occupied-Ecaz displacement of a
+living ordinary Duke grant also resolves uncertainty. This is a provisional
+online policy, with broader interactions and deployed verification still open.
+[Scope](ECAZ_DUKE_ACQUISITION.md#public-first-turn-proof-and-occupied-ecaz-displacement--29-october-2026).
+
 ## Public resolution of Duke capture uncertainty — 29 October 2026
 
 A revealed ordinary Duke battle or named public revival, acquisition or death resolves the prior
 capture uncertainty; a later possible Harkonnen capture can restore it. This
-is a provisional online policy and does not infer legacy capture history.
+is a provisional online policy; the bounded first-turn public proof above also
+applies to eligible unstamped legacy games.
 [Scope](ECAZ_DUKE_ACQUISITION.md#public-resolution-of-capture-uncertainty--29-october-2026).
 
 ## Duke Ambassador capture uncertainty — 29 October 2026
@@ -12,7 +22,8 @@ is a provisional online policy and does not infer legacy capture history.
 Fresh games record whether a public capture could have involved Duke, without
 using the secret selection. Direct acquisition and automatic alliance loan
 are uniformly guarded while that history is uncertain; legacy games without
-the receipt remain conservative. This is a provisional online policy.
+the receipt remain conservative except where the first-turn public proof above
+applies. This is a provisional online policy.
 [Scope](ECAZ_DUKE_ACQUISITION.md#public-capture-uncertainty--29-october-2026).
 
 ## Concealed Duke and Ghola guidance — 29 October 2026