diff --git a/src/4cade.init.a b/src/4cade.init.a
index 88476543a..b66669aa0 100644
--- a/src/4cade.init.a
+++ b/src/4cade.init.a
@@ -330,6 +330,19 @@ PrintAsDecimal
 OneTimeSetup
          lda   zpMachineStatus
          sta   MachineStatus         ; save machine status in LC RAM
+         and   #IS_IIGS
+         beq   @NotGSOS
+!cpu 65816
+         lda   $E100BD               ; Make sure GS/OS was the boot OS
+!cpu 6502
+         beq   @NotGSOS
+         ldx   #5
+-        lda   QuitToGSOS,x
+         sta   PatchQuit,x
+         dex
+         bpl   -
+@NotGSOS
+
          ldy   #$0b
 CopyDevs
          lda   $BF13,y
@@ -439,3 +452,10 @@ CopyDevs
          !byte 100
          !byte 10
          !byte 1
+
+QuitToGSOS
+!cpu 65816
+         clc
+         xce
+         jmp   $E0D000
+!cpu 6502
diff --git a/src/constants.a b/src/constants.a
index f42e9e095..3d1c50993 100644
--- a/src/constants.a
+++ b/src/constants.a
@@ -8,7 +8,7 @@
 ; LC RAM BANK 1
 ; D000..E908 - persistent data structures (gGlobalPrefsStore, gGamesListStore)
 ; ...unused...
-; E926..FFF1 - main program code
+; E914..FFF1 - main program code
 ; FFF2..FFF9 - API functions and global constants available for main program
 ;              code, prelaunchers, transition effects, &c.
 ;              (Wait/UnwaitForVBL, MockingboardStuff, MachineStatus)
diff --git a/src/ui.reboot.a b/src/ui.reboot.a
index 49c78bfd1..7dc4b78fe 100644
--- a/src/ui.reboot.a
+++ b/src/ui.reboot.a
@@ -17,6 +17,7 @@
 OnQuit
          jsr   SwitchToBank2
          jsr   EnableAcceleratorAndSwitchToBank1
+PatchQuit
          inc   $101       ; bank in ROM
          +LDADDR ROM_REBOOT
          +ST16 $104