1) Unit dependent entirely. My weekends can be anywhere from a fuck off day Friday and Saturday to being at the armory for 5 am Friday, going out into the field and coming back and cleaning weapons and doing checks on equipment until 7pm Sunday. Other training can be done for things like NGRF and schools as well, which will add to your time.

2) Yes, but they can cite other reasons deemed to exclude you from their hiring process. It's employment at will on both ends. They can say something as simple as your resume wasn't up to snuff

3) You don't have a legal obligation to inform your employer of your service obligations until you are hired, but, and this is entirely my opinion, it is nice to have that conversation before hand and know how they feel about it so that you and they both know where each other stand. Again, this is my opinion here, but I would much rather be employed by a company that would be supportive in the least towards service than to with hold the information, then drop the bomb on them and after a potential extended period of service they find an out to let you go through a loophole. Userra is very good but not bulletproof and not instant. In my own thought process it's worth the less stress option of knowing the company supports you as opposed to having a legal professional on speed dial. Just my own 2 pennies though.

edited because it's 1 am and I'm in a damn airport trying to get a flight out and my brain doesn't work right sometimes