Hi all,
Here is how to edit and change the number of turns per year for Rome II total war.
First, open up your startpos.esf using your ESF editor. This file is located in your data folder/main_campaign
Then click on CAMPAIGN_STARTPOS > COMPRESSED_DATA > CAMPAIGN_ENV > CAMPAIGN_MODEL > CAMPAIGN_CALENDAR > then change the first number from 1 to whatever number of turns per year you want.
Enjoy
EDIT: This will not affect your research or build time as research and build time are per turn and not affected by the time scale.