The question is:
Is QRH’s company interpreting the rules correctly?
As I understand it they take the length of time you are on duty i.e. from 14:30 to 03:15 (12:45) and reduce this by the length of the break claiming it does not count as FDP. I.e. 12:30 – 3:15 = 9:30.
I believe this to be wrong because:
Subpart Q Section 1.6 of definitions states:
The FDP starts when the crew member is required by an operator to report for a flight or a series of flights; it finishes at the end of the last flight on which he/she is an operating crew member.
To not count as a duty the break would have to be a minimum of 12 hours or the length of the preceding duty whichever is the greater.
Thus your break is less than that required for minimum rest therefore it has to count as FDP as defined above in 1.6.
The regulations for split duty are granted by the authority to an operator and are therefore a 'local agreement’, and should be in your ops manual or equivalent document.
If we use your figures then the break of 3:15 counts as an extension of 1:37.5. Therefore your duty should end after 11:30 +1:37.5 = 13:07.5. I.e. at 03:37.
However as this ends in the WOCL there is acording to your figures a 1 hour reduction ie 12:07 with a finish at 02:37.
Your planned duty is therefore illegal – however check your ops manuals or equivalent very carefully to double check as differences from sub part q may be allowed. (The definition of what counts as FDP should be the same and therefore the break counts as part of the FDP the same as if you were positioning during that period.)