This new firmware was supposed to fix it but if anything it's worse than in 12.23.
For reference it predicts 17:28, 36:49, 1:21,20, and 2:54.23 respectively.
I just ran a 2:40 marathon 2 weeks ago, and many many halfs in training at MP (mid 1:18s) and it barely nudged down. 3 weeks ago I ran a not-all out 16:36 5k, and just yesterday I ran another half 1:17 not all out (first one in the new 12.27).
I've completely given up trying to reason any data out of any of this. with HR drift I also reached "200" a few times, which is hard being 40 and all, and my stamina went down to 1% around the 1 hr mark lol.
I want to tell myself this was worth upgrading and it seemed to work for a little while but argh so frustrating. Is it just my unit? do I have a lemon or is this all hot garbage?
I'm experienced enough that this isn't going to tell me my fitness etc but I'd like some sort of consistency there. the new firmware actually made everything 'jump' up slower.