TCF...Congratulations....Given the choice of a solo row of the Atlantic Ocean and Qatar Airways desk job... I see you took the harder option.
Depending on your experiances as a pilot at previous airlines will depend your depth of tolerance factor and your length of employment in the Gulf.
From your posts you seem to be making all the right noises as far as crews are concerned and you are well aware of the need to go with the flow and roll with the punches...the problem will be if you have a burning desire to achieve anything....anything that is other than a monthly pay cheque and investing offshore your UK pension in a taxfree climate.
You will be well advised to get your nonresidence from the UK tax system confirmed in writing by the UK tax man...if you do not have a written contract of employment you could find he considers you still Uk resident for years.
Danger lurks.... if you get seriously ill... you have to hope that Qatar Airways like you enough to fly you out to the UK for treatment...i.e. dump you back from wence you came.... you could find (like my friend Rad Gammage did at Gulf Air that they do not...but then he had only done 31years service for them as pilot.
If dumped back in the UK you will have to pay fully the NHS for any hospital treatment because you have been nonresident UK the previous tax year...the NHS will ask you to prove your residency for free treatment if you cannot they will charge you mega bucks and if you claim residency the Tax man has got you.
You would be well adviced to note the £ amount of medical insurance you "might" be allowed in your contract..if you have an old pilot health breakdown "event" healthwise in 40degrees C OAT.
You sound the sort of nice sociable type of Uk guy who would jog and play sports etc in such conditions.
The UK tax man will always wish you to prove... if you were resident or non resident...this is a pain if all the time you "thought" you were offshore and non resident.
You might be better advised to establish a tax residentcy in the IOM and show yourself based there and pay tax there... which will be minimal and also retain your NHS cover and have your UK state pension payed into the IOM and start working on your UK domicile change to mitigate future IHTand sell up everythying in the UK.
You sound nice enough to be divorced as all real pilots are....if you are taking the second/third young wife there (your age minus 25yearsish) and any kids that need education to Qatar your employment is unlikely to be cost effective.
If you have always lived in the UK your life is about to slowly get very interesting in the wrong direction....hats off to you if you achieve three years plus of flying a desk in Qatar and manage to return a non racist and not extreame right wing this will indeed be an achievement...the good news is you will appreciate the UK/IOM more for a few months on your return.
We had loads of guys arrive with your keeness at GF to fly desks in retirement
on BA/Cathay/Air Newzland pensions...most did not make twelve months...one we considered a terminal basket case and clinically dead on arrival managed two years then died within days of returning to NZ.
Probably you do not want to go this route.... anyway whatever you chose I wish you good luck..just remember ...Your Contract terms and conditions mean very little East of Dover and are considered by Arab employers of expats as a point from which to ratchet down after you have made the move to the Gulf.