On average how many days a month can a new guy expect to be on reserve in BWI?

I live on Long Island there are several flights per day to BWI

14, 15, or 16 days depending on length of the month

I know this is really variable depending on time of year, base, etc. but I would appreciate if you have examples of how much you have been used on reserve. Say DAL in the fall. Thx

That's hard to say. It used to be up until October last year that you'd always get used on reserve. Then the classics were retired and upgrades didn't happen and manning lead to manning on the FO side to go really high. November - February reserves weren't being used that much, and you'd see multiple bids for reserve blocks in open time (never happens usually). It looks like for April reserve coverage is much lower then in recent months so maybe things are returning to normal where reserves fly most days.

In 2017, 25% of all my Reserve was spent from the couch. Heard stories of guys junior to me not flying for the entire month. YMMV, but I don’t expect it to last, for reasons previously stated.

Been used 7 of 16 days this month, assuming I don’t fly tomorrow. Looking good so far.

In more junior bases it may be better, with more commuters with a “fly” preference. Pretty much everyone is “pass” here. Plus there seems to be a big difference between reserve blocks that start Friday/Saturday compared to weekdays.

Yes. Start day of the week seems to make a big difference. I sure haven’t figured out the pattern though. Your pass preference and seniority are basically the last things looked at after matching trip length to reserve days in the block and how many duty periods you’ve been used for the month. Just pack for a 4-day every time, assume you are getting a call to fly, and be pleasantly surprised if it doesn’t happen.