An update on this issue:
Car has continued to flare and clunk badly on 2nd gear. Have learned to live with it and drive accordingly. But after a period of constant bad shifts the Transmission service light came on again.
This time I decided to try clearing the adaptive settings and doing the new adaptation process with VIDA.
When I changed the fluid in May 2019 I used the dipstick at room temp. So this time (9 months & 6000K later) I used VIDA to tell me when tranny fluid was 85 degrees and found the fluid was low. It needed another 400ml. Topped it up and reset the oil counter again. DTC's showed SLT solenoid was cause of flared or abrupt shifts.
Upon clearing codes and resetting the old adaptation settings back to factory setting the car drove much better; in fact it felt like a different car. But after doing the full adaptation (hardest part was finding quiet and long level roads so you can do the adaptation properly) it was ok but perhaps not quite as good as the factory setting. I've been driving around with it now and its only flared slightly once in the last 1000k's
Fingers crossed it stays that way otherwise I'll be doing the valve body nest.
