Maneuver for orbital transfer breaks after reloading if two stages participate

[mmix]

Initially the maneuver detected a stage change and was counting dV down properly.

However, I messed up and reloaded to a point after I created the maneuver but before the burn, and the maneuver is now broken. It does not show stage change, and it does not count spent dV properly any more, so no idea when to turn off the next stage.

 

I can provide a save file if needed.