That's what it is then.
A converter drainback problem goes away in a few seconds weather it's cold or warm does not matter.
Hardening rubber parts work great warm but not cold.
Basically they call it "a soft parts rebuild" meaning nothing broken, just needs it's rubber parts replaced mostly.
That said, I wouldn't even think to do something about it without planning on new clutches and a front band at the very least. (well, front and rear seals also of course)
Sounds like that 4 speed may happen sooner, but the automatic could do what it's doing for a long time before it actually quits engaging completely.
