In Thrawn's Revenge there are space battles, and then it jumps to land battles. I think that in space battle if you lose too many ships it should automatically retreat your forces below the planet's atmosphere. Once it does that, it provides a few support units (Like adding a few nebulons and a few corvettes for the Republic but for the Empire it gives a Victory Star Destroyer). Then it continues the battle. Sort of like Battlefront on the PS4.