I have a 955 with beta 14.13. I also use a 530 for cycling (beta 9.73).
I run and/or ride most days, and VO2 max is tracked via both.
TrueUp is toggled on for my 530, but I notice that the TrueUp toggle is missing in my 955 from where the manual says it should be (System > Physio TrueUp). My menu skips it entirely in the list of options (see manual, page 108).
I believe the TrueUp has been missing for an least a couple of betas.
There is a mismatch in training load reported between by 955 and the 530, and generally TrueUp and training status is mismatched and a bit broken.
Any similar reports or experiences? Not impressed. This all used to work sweetly with my 745M....