If you've already done some exams I would personally continue with them and only delay your last sitting. Leave 1-2 easy exams (comms I/V or m&b ) such that you can do learn and pass them on short notice.
Don't get into the situation where you don't have enough time to master+pass your last subjects because you've delayed doing sittings or studying them. Once the 18 months have passed all your previous results will be rendered invalid.
If you haven't sat any exams at all, something to consider is that ECQB7.0 is coming soon (deadline april 2021, I believe), which implements some major changes regarding learning objectives and subjects (comms will become 1 subject for instance).
Why do it before ECQB7.0? if you start now you will finish all your sittings under the old learning objectives and ECQB6.0, which will presumably no longer get updated and hence all questions will be available to study, via third party questionbanks such as aviationexam, bgs, atplquestions etc.
Once the new ECQB arrives the third party banks might require a while to get up-to date, as they rely on students' feedbacks... knowing EASA, you will still require questionbanks to pass your ATPLs in the future.
The use of questionbanks usually gets a load of **** from oldtimers, but with the way EASA has currently set up their exams they have become a neccesity to pass some of the subjects. I've literally encountered questions (on my actual exams) about one sentence in my 500 page book.
Don't get me wrong: you should study the subject, however some questions are simply ment for memorization from bank and will have no practical use for your career. e.g. min. regulatory distance between taxiway lights....
Last edited by African_TrouserSnake; 30th Jul 2020 at 00:33.