I have my autosave_every setting at 12 in Simutrans\Config\simuconf.tab and no setting in the pakset simuconf.tab. Nevertheless, I only get one autosave per year instead of the usual one every twelve months.
I am very confused... a year is 12 months long. One autosave per year is the same as one autosave per twelve months...
I saw your comment, and immediately realised my mistake... :o
I had 12x a year confused with every 12 months.
Sorry to bother you, my mistake... :-[ :-[