ok. I was wondering of there was 30 minutes past chocks on. The home airline abandoned 1,5 LH briefs about 10 years ago. All of this briefing / reporting time is a bit shady, it depends how honest is the operator with the crew-room to A/C part of the equation. Some FDP-critical missions would only have 45 min briefing time allocated but that is quite far from your question.
Meanwhile, I found this: a starting point?
ARO.OPS.235 Approval of individual flight time specification schemes
(a) The competent authority shall approve flight time specification schemes proposed by CAT
operators if the operator demonstrates compliance with Regulation (EC) No 216/2008 and Subpart
FTL of Annex III to this Regulation.
(b) Whenever a flight time specification scheme proposed by an operator deviates from the
applicable certification specifications issued by the Agency, the competent authority shall apply
the procedure described in Article 22(2) of Regulation (EC) No 216/2008.
(c) Whenever a flight time specification scheme proposed by an operator derogates from applicable
implementing rules, the competent authority shall apply the procedure described in Article 14(6)
of Regulation (EC) No 216/2008.
(d) Approved deviations or derogations shall be subject, after being applied, to an assessment to
determine whether such deviations or derogations should be confirmed or amended. The
competent authority and the Agency shall conduct an independent assessment based on
information provided by the operator. The assessment shall be proportionate, transparent and
based on scientific principles and knowledge.
GM1 ARO.OPS.235(b);(c) Approval of individual flight time specification schemes
ICAO DOC 9966 (MANUAL FOR THE OVERSIGHT OF FATIGUE MANAGEMENT APPROACHES)
Further guidance on fatigue risk management processes, appropriate fatigue management, the
underlying scientific principles and operational knowledge may be found in ICAO Doc 9966 (Manual for
the Oversight of Fatigue Management Approaches).