I use initial 1 or greater with no effect, as you said.
I don't get any related error messages. Only messages I take (sometimes) are these:
Code:
13:21:00.046 [script.err] [error] Script Error in HundredYearWar_0.99/data/world/maps/campaign/imperial_campaign/descr_strat.txt, at line 3507, column 1
The character record Prince Gonηalo is set as faction heir but is not in the family tree.
13:21:00.046 [script.err] [error] Script Error in HundredYearWar_0.99/data/world/maps/campaign/imperial_campaign/descr_strat.txt, at line 3929, column 1
The character record Prince Laureyns is set as faction heir but is not in the family tree.
But this should have nothing to do with mercenaries, right?
In my mod, I use a new campaign map and a new starting date. Could this cause the problem?
I don't use start_year/end_year in my mercenaries entries.