I flew at 30 weeks in my last pregnancy. Most airlines just require a “fit to fly” form to be signed by your midwife!
Check the airlines policy as each will have slight variations. Most will let you fly until 36 weeks if a single pregnancy. So if you are going for two weeks you will need to be 36 weeks when you fly home. Anything after 28 weeks you will need a fit to fly letter from your midwife.
Online it says 36 weeks is the latest you can fly unless you’re expecting multiples then it’s 32 weeks!