Does the 2-3 flare happen sometimes or all the time?

Last night pulling out from a traffic light I gave the SVX some gas. It seemed like when shifting from 2-3 the RPMs went up to about 5000 or so and then it shifted. Maybe it hopped back into first, I don't know. But that scared me so I tried accelerating hard around the 2-3 shift but I couldn't get it to happen again. When the tranny starts to go and the 2-3 shift flare pops up, does it happen all the time or once every now and then until it is more frequent and then the tranny dies? I just changed my tranny oil and now this is happening?!