First of all, I think this is one of the best features to ever be added in an FM. I completely adds to how I look at saves. I was so happy with FM11 I wasn't going to buy FM12, but the ability to add/remove leagues convinced me to get FM12.
Was basically wondering how this works on a technical level.
I manage in Switzerland at the moment...so say I get a job offered in Italy and decided to remove the Swiss league, the game simply stops generating fixtures for the Swiss league...however the database stays there? Are my achievements/reputation in Switzerland affected in anyway? And if I want to return to Switzerland, the game simply starts generating fixtures again?