If you don't have JCAB ATPL you have about 1% odds of being hired as a DEC. Normal turnover is about 10% a year, I think last 18 months it has been slightly less than that.
We have plenty of Captains, still a lot Captain-Captain flying. Need more FO's.
If you want the job, get hired as an FO and upgrade near the end of the first contract.