So in my 3rd class medical there is a section that says “if you meet all of the requirements for recertification and are otherwise “medically” qualified, your HIMS AME is authorized to special issue an airmen medical cert for 6 months (could be a year) for ANY class of pilot duties”
Ahhhh so easy!! Nope
But the requirements for a HIMS 3rd and 1st are different. 1st class will require a HIMS trained psych and the full neuro cognitive battery with a HIMS neuropsychologist. My current problem is that I was issued a 3rd class SI and then my AME gave me a 1st class at one of my exams which triggered a nasty letter from OK for the neuro battery. Nasty as in - get this done in 60 days or else. So in short, things got overlooked, my AME rushed and sent in something that shouldn’t have been sent in and now I have a withdrawn special issuance - aka grounded.
In short, yes you can upgrade but if you don’t have a HIMS “federal level / grade” psych evaluation AND the neurocog psychological side done, it will just bite you down the road . Make sure your AME directs you to get the right exams done up front with the right professionals and then sends in everything for the upgrade. Get it done early as 1st class HIMS take an extra 3ish months vs 3rd class.
I flew over 1000 hours building time in 12 months to go to the airlines and now I’m sitting around trying to straighten out the doodoo 9 months later. Sucks!!!!
1st class HIMS cases are worked out of DC and take longer
3rd class HIMS are worked out of OKC and generally are faster.