Thankyou for the info so far...
Gary, my reason for looking at this situation now is that if getting the hours just after joining means waiting 6mths for the chance to do an ATPL skills test (out of sequence LPC) then this has some financial effect. If on the other hand everything was do-able any time you got the hours then it wouldn't be as important. From the answers given, it looks as if it is a bit important.
As direct entry FO this means missing out on £7465pa worth of salary, or an extra £622 per month before tax. This is taking the 90% business into account. In my book that is money worth considering.
Just hope I can have those hours before joining, then use the first EZY LPC as ATPL skill test. I don't have LPC due in my current job before joining EZY.
Cheers everyone.