OTR
The CAA (and the Company) will audit the FTL as part of normal compliance process. This is done normally to look for trends e.g. XXX-BBB-XXX flight runs seasonally and discretion was xx %. If its over 25% (might be 33%) then remedial action will need to be put in place, at the very least in time for next season. Airlines don't in general "tweak" the schedules because of On Time Perf and the risk that a bent block/schedule will impact it / slots / EU delay comp rules etc - This is unlike the old days when it was more common practice.
The issue is this schedule was a one off so harder to look for unless the CAA had the Company under closer scrutiny from previous audits. In this case they might have well unearthed it.
From my knowledge of TC their employees including Pilots they are no where in this bracket and it may have been a simple case of someone trying to do their best. Yes the schedule was unrealistic but how many times do you work to the max at TC - not when your going to PMI and back.
It then snowballed into us v them which is a great shame.