1st - a Weekend BMQ takes about 11 weekends, so you should end up with 22 days (not includeing friday nights). What I find strange is that they told you every other weekend in Jan and Feb, unless there is some special deal for officers that would not give enough time. You might want to check up on that point.
2nd Physical fitness training will depend on how the course is run. That said, I would strongly suggest you train yourself to be able to run 5 Km when you show up. Do your push up, sit up and chin ups (as you already know). Due to it being ran on weekends, the course won‘t make you fit, but will give you a reason to stay fit on your own time. Also, if your not marching from class to class...you will be running. Go on hikes with a weighted back pack (work up to 25Kg). However, be very careful not to hurt yourself. Get a check up...follow a program....there a lot of websites out there that can provide good fitness programs...do your homework. Try http://www.bodyresults.com/index.asp
3rd - Course content will include, drill (marching), service rifle (C7), Rank sturcture, hygine, Dress regulations, general military knowledge, Nuclear/Biological and Chemical warfare. Just to name a few. As you can see other then Rank Structure....there is not much you can prepair for.
You should be receiveing what‘s called "Joining Insturctions". They contain most of the info you will need regarding what to bring, wear, and basic preperation like writing an autobiography. If you have not received one a few weeks prior to your course, call you unit and ask for it. Its important!
Summer and winter courses have big differences. You can get more accomplished on a summer course and your fitness will improve because it is continuous...not broken up on weekends like winter courses. However, in the end (at the BMQ level), you will know pretty much the same as your summer conterpart. The Teaching objectives are the same. The trick on a weekend course is to keep your head in the books studying and practicing what you have learned...try and stay in the military frame of mind as best you can between weekends. Practice drill for example, work on your uniform and boots. You have to arrive every Friday night switched on, you don‘t have the time to switch from a civi to military frame of mind...must be there already.
All I can say is read up on what ever general military info can find, Read stuff on CF rank structure and work on your fitness. If your really lucky, maybe you will get a few briefings from your unit on how to wear the uniform and some basic drill lessons to help you do well....no harm in asking.
If you need more, email me at atoms15@hotmail.com