I have never been a fan of conformance.
Now there is a requirement for passport checks if you have OLCI'd, I think there is an argument for making the conformance time the time of your first interaction with the DCS/check-in system at the airport, be it SSCI, bag drop, passport check or entering the security area.
I'd also be happier if the conformance time was T-30 not T-35 - for a lot of airlines is T-30 still the latest a business class/premium passenger can check in with hand baggage only.
I'd be even happier still if conformance was not enforced and offloads happened if you were not checked in at all at T-30 for short haul/T-45 for long haul, or were not at the gate at T-20. Other airports manage something like this perfectly well.