I just realized that seatcounter and some other bucket tool I was using a couple months ago didn't show S-class for any Frontier flight I checked. I'm wondering if it's a different letter across systems. I'm toying with the idea of transfering Amex MR>Frontier again, but there has to be a better way to check beforehand. I tried the ER phone number an hour or so ago and waited way too long for no answer. I'm flexible on the dates somewhat. DCA-LAS 8/1-3 and LAS-DCA 8/16-18. It'd have to be US-bad to not have anything, and I haven't seen many complaints at all here. Any idea on availability in this these ranges? I might try the phone again this week. The 15k level is just too tempting for me to not check specific dates.