Anonymous...cool out there tiger.
2nd, and this is for everyone...contracts are mostly not worth the paper their printed on. They are primarily a basis for your employment and not always completely binding due to the fact they are drawn up by a lawyer who writes it to be as tangable as they wish. Be warned, dont put all your faith on your contract...most crew experience with this will tell you they've been screwed based on how binding they thought their agreement was.
3rd... Garrick, Before taking this probation, it should have been defined by your captain or managing personell under what terms you should be taking leave..but its probably too late for that. If so you should be spending your time investigating your options. Being under probation means you may not have a gig in a month so keep your eye out for another opptunity or consider looking into upgrading licenses during this time.
Good luck man...I know how much of a pain this situation can be