are your bosses a bit dim then? surely if all their employees take annual leave in these three months, there wouldn't be anyone left to run the company!!! as far as i am aware, you are entitled to take your leave whenever you like. where i work, the only stipulation is that a maximum of 4 people are off at any one time (out of a team of 25) or you need to discuss things with the manager, who will do his best to accommodate our needs outside of this. at the end of the day, how can they stipulate how you spend your spare time? there has to be some kind of legal support for you here, but i am afraid i don't know for sure. good luck!