Last night I was setting up for an invasion of Dalmatia in a war between Italy and Austria. The invasion triggered in the next turn and AH accepted, but I didn't want to play the battle until today so I exited out. I was curious to see if it would trigger again so I reloaded the game and sure enough it did, but when I accepted the battle AH this time declined and the next turn rolled over. I didn't save, just exited to pick up the next day.
Jump forward to today, when I went to continue the turn, I receive the following error and find that land combat is now ongoing in Dalmatia. I get this message even if I remove Dalmatia as the invasion target. Furthermore, I get several odd battles during this turn (I tried reloading and changing turn several times). Once I got an AH invasion battle of Southwest Africa, way outside their range. Other times I get an AH invasion battle of East Coast Italy - which is my home area.
On version 1.22. Using the Alternative speeds mod, AI capital ships designs mod, and the 1900shipnames mods.
Update: I was able to fix things by editing the Map Data file and changing the following lines under the Dalmatia section
MapArea1Possession15Invaded=1 to MapArea1Possession15Invaded=-1 MapArea1Possession15InvasionSupport=1 to MapArea1Possession15InvasionSupport=0
However I'm still reporting this a bug because it should not have happened and because of the weird invasion battles I was getting. I was also getting invasion battles to invade Austria-Hungary itself.