I think I understand now how GPxPatch handles lap records: It's in the doc of GPxTrack (html readme), it uses ini files with [Tags] definitions. Records are then saved in F1gstate.sav and get updated for the CURRENT season you are playing. What appears in the Workshop menu are the OVERALL records instead. It would be logical if GP4 is updating these overall records after finishing a season (I vaguely remember F1GP and GP2 doing the same, but not sure).
To see the provisory lap records, I use the Record Editor whcih will show me 4 lines: 2 lines for the overall records that remain constant (until finishing a season?) and 2 lines for a '2000' season but this one is the current season you are playing. Record Editor uses only the default tracks, so if you play a mod you just have to remember what track nr.1 or track nr.x in you mod actually is.
XenonS