stick a leave pass in for any leave that you are entitled to. it has to be signed, either in acceptance or rejection. this at least means that you wont lose any leave when carrying over from one leave year to another.
i think that technically (feel free to correct me here) the mod doesnt have to give you your leave though, all to do with QRs' etc. how this would stand up though when challenged in the courts is anyones guess.
the main thing is to get those leave passes officially rejected so that the stats are there for all to see.