Since this is the first time visitors thread, I'll just point out that the "times of release" sign is totally a thing I've seen in some bakeries and fresh desserts shops. There can be queues for release timings but I kind of think Japanese will sometimes queue for the sake of queueing, more based on the hotness/ranking regardless of the quality or actual desirability of the item. So don't solely go by the "it's full/there's a line, it must be good" rule of thumb which can work elsewhere without checking what you're queueing for.