This is the kind of nugget that I love.

Not every day 'off' is a RES 'non-fly day'. Example: the last day of a REG month before starting a RES month, even if you're not flying, is not a RES 'non-fly day'. You are not contactable and have no required schedule check.

If you are on RES on the 1st day of the new bid period coming from REG you have no required schedule check and you're not even required to 'ascertain if something's been put on your schedule'. CS must legally contact you for any assignment and that assignment can not commence prior to 18 hours on the first. Robo CNO call can be used to escalate you to SC at RES bid period minute-1, but can't be used for a trip. (see "Legal notification")

Please correct me if I'm mistaken as I go back and forth, and will intentionally 'orphan' RES days at the beginning of the new bid period.