All new entrants to easyJet irrespective of base whom commence an induction post March 2019 will be required to hold an Austrian issued licence. This isn’t an L3 requirement at all, it’s actually asked of by the airline - given it be written on their orange letterhead (in my case).
Any existing U.K. based employees or any new and UK based employees starting work, but not training, before March can retain the UK CAA papers. A trainee starting their course soon would finish after March 2019 and thus require Austrian papers.
@David.98 - i’d ask the individual or organisation that’s asked you to do this for guidance. As others have said, a medical state of issue is just a paper or two to adjust.
Hope this helps.