Hi, no not every month. I don't remember the pattern. It's usually the last Thursday-Saturday of the month (starts Wednesday for cardholders) but they take some months off. I'm pretty sure they don't do it March or April, and I know they do it September, October, day after Thanksgiving, New Years Day and in January and February. The rest of the months I usually just go to the site on that Wednesday to see.
It is either an extra 30%, 40% or 50% (50% only for New Years and day after Christmas) off the already marked down price depending on what corporate decides I assume. The already marked down prices are 30%, 50% and then 65% off retail, so there are some deals to be found! The wallets I got were 65% then 40% off