Please understand that in today's World the legal movement of Parrot (Birds) can change rapidly! If I recall correctly, this Spring no Birds where allowed from specific areas of Western Europe because of both over Winter and Migration occurrence of Bird Flu! There had also been a couple of Hot Spots in North America.
So, as we move though the more stable Summer months, Falls Migration is coming onto the Horizon! Regardless of whether you have all the Paperwork, if a Country elects to halt movement of 'Birds' You are either not leaving or not entering that Country regardless of your Parrot's specific Status!
All of the Health Certificates that I have seen are for a 30 day window. Once that period ends, you are required to obtain a new certificate! If you are outside of your Home Country, your will have to get a Health Certificate from a 'Certified Avian Vet' in the Country you are located.
As Stated above, you really need to be working with the Country's that you will be traveling too! It would be recommended that you include those Countries surrounding the one you are visiting just in case your flight is routed to another Country!
The World is no longer a simple place, traveling is now demanding! Those unprepared will suffer!
FYI: Proof of Ownership is much more demanding in Europe than currently in North America! Assure that you have the needed documents (in addition to all the others) to prove Ownership of your Parrot! A long and supportable yearly use of an Avian Vet is of great help in creating the document base! If your Parrot was hatched on or since 2, January 2017, you need to have the Birth Document and Purchase Receipt of your Parrot.
Showing up at the Airport and traveling the World! Is today: Once Upon A Time thinking! Being over prepared is what work!