For Reservists, what amount of time is appropriate to spend working on stuff OUTSIDE of BA?

As a Battalion Commander, it's literally like a second full time job. I can honestly say that I do work EVERY single weekday, things like signing approvals, etc. I expect my Commanders to check their email daily or every other day or so. I would expect their troops to check it weekly at a minimum. What about you???

MAJ Rahman,
This is a very relevant question. And one that I am in the process or recalibrating my attitude towards.

Over the last two years in BN CMD (rotated out beginning of May), you got it exactly right - it was a second full time job. During the 1st year, I think I literally put in 40+ hours a week (4+ hours every weekday, most of most weekends). During the second year, I got the hang of it and maintained at around 20-25 hours a week, getting less over time. Over the last month or so, I've had so much time I haven't known what to do with it.

I drive down to my new unit tomorrow (all freaking day....) and have my first BTA back in the land of staff. But its a somewhat operational unit, so I don't know the battle rhythm yet. I'd be surprised if it was less than 10 hours. 10 hours is my goal - an hour day in the morning/PM and then half a weekend day.

Of course, I will also be doing AWC in my spare time....

I think 5+ hours a week is the absolute minimum for anyone in a leadership role, with at least daily checks of enterprise email. Anything less and you lose situational awareness. For others I would say check email at least every 2-3 days.

We had bi-monthly staff calls and were usually there the Tue prior to drill for pre-ex checks. After a while though, especially after deployment orders were in hand, it was like "for the flag" became an actual pay status