TH350 1-2 shift delay

[Chad E532]

This past weekend I had the car out for the first time this year and had some odd shifting delays.
On the first pass of the day it shifted 1-2 right on with my movement of the shifter. On the subsequent runs the car would run about 500-700 RPM above the shift RPM when looking back at the playback. I know there could have been some delay in the drivers seat on shifting compared to the light but it happened on 3 runs in a row and I was intently watching the shift light.
In the pits shifting from 1-2 at 3000-4000 rpms it shifts instantly but on the track under load trying to shift at 6600 and the playback was showing up around 7100. I bumped my light down to 6300 to try and short shift it and it still went to 7100.

I am thinking it might be best to start working on a spare transmission quickly to get this one out of the car and in for repairs itself.

Any ideas on if this is a steel/friction slippage issue or if it could be valve body related?

Thanks,
Chad