Yep. My Sat AM flight was cancelled while on the parking shuttle bus, they had two 6ish AM departures, but only one plane and just discovered that at 4AM. They then calmed it was auto-rescheduled on line but the ticket agent admitted they all said that and they hadn’t seen one with a valid reschedule.
I was assured it would take 24-36 hours to get back to normal. They cancelled my rescheduled Tues afternoon flight, claimed it “weather” and won’t show any options to reschedule departure until 5 PM on the the 31st. I gave up and put in a request to cancel the trip, they acknowledged it, yet I just an email reminding me of my apparently still valid return ticket, that would leave TPA at 1 PM, 4 hours before any theoretical flight to TPA would take off.
I ‘HEARD’ that the Southwest problems were due to not having any partnerships with other airlines for rescheduling. The system is called (IIRC) the Hub and Spokes policy. The other airlines were able to schedule some passengers on other airlines that they partner with. Southwest has no ‘partners’ so could not reschedule on other airlines.