I'm having strange issues with bulk emails since upgrade to 5.48.0. I'm using the traditional mailer, and not Mosaico. These issues do not appear if the list is small (or maybe it's certain configurations?? Maybe it's the use of variables in the template?).
A scheduled mailing does not show in the list. But then I go and flush the cache (cv flush) and it shows up as scheduled.
Have to cancel mailing if it hangs. I have now throttled sending to batches of 200, and then it can manage to go, but takes forever.