habcer,
Remember there is no such thing as an fATPL, its a colloquialism for CPL/IR with ATPL examinations passed.
Therefore, as long as you keep your CPL current, your MEP rating and IR valid, you're still employable.
For definitive answers have a good look in LASORS.
Click here for the link to LASORS
Assuming that you're flying in your spare time; the main issue normally is keeping the IR and the MEP rating current, since it is the most expensive part of flying.
Keep flying, you need to be building hours. Apparently, airlines don't look favourably on people that qualify with the fATPL, then do little flying thereafter.
Hope this helps,
POL.