Corections
Yes it is 90 days, it is the "tourist" visa that is now 30 days...
The validation is to permit time for the medical, and air law to be passed.
Your sponsor, assuming they are not totally brain dead, should be ablew to start your residence visa processing, they will need a copy of your passport, plus a quantity of passport size pictures.
Then if they are very efficient you can collect your visa after your notice period.
The GCAA do require sight of original logbooks etc, but this can be done when you arrive, you will only save a few days at the best.
You might wish to discuss with your UAE Sponsor, a few days off duty vacation trip, to visit DXB, and deliver your original docs to GCAA.
I assume you have a current class 1 mewdical, whatever this is I assume ICAO, in tandem with your base licence, this ios what they want to see.....for your validation.
Also get organised from your Local CAA a "verification letter", or if FAA a print from the pilot records.
Remember to get level 4 to 6 English documentation too.
keep pushing......glf