Always use 27ms/tick in wallclock timing mode

src/saveload/afterload.cpp

@@ -670,6 +670,7 @@ bool AfterLoadGame()
 	TileIndex map_size = MapSize();
 
 	UpdateEffectiveDayLengthFactor();
+	SetupTickRate();
 
 	extern TileIndex _cur_tileloop_tile; // From landscape.cpp.
 	/* The LFSR used in RunTileLoop iteration cannot have a zeroed state, make it non-zeroed. */