Mine are like Paul P's, no pending end time. We're all on different email marketing lists, and with no offense intended, I'm certain that the database is a bit confused based on how many people want emails but don't get them.
In my own case, I've had periods of getting dupes, periods of no emails. It's possible that those getting the "act now" emails meet certain past buying behavior criteria and the rest of us meet other criteria. Also possible that Cake is testing to see how those types of messages drive buying behavior differently than less coercive emails.
Doesn't matter. We are responsible for when we buy, not the emails. Personally, I'd appreciate knowing the deadline with about a month's notice so I can choose/buy in a relaxed and easy manner.