Hello Greg, thanks for your reply.
I cleared all codes, watched the transmission warning light disappear and took a drive first through the city and out into the countryside.
After about thirty minutes I noticed the first "missed" shift, and the transmission light came back on.
The problem was still not consistent, as it would change up past 2nd now and then on the way back.
I only got one ODB code when I got back, and that was number P0732,