Try to finish the ATPLs before leaving your integrated course, it will save you a whole lot of trouble.
Otherwise you'll have to obtain a PPL first (=go trough PPL theoretical + PPL Practical) before you can restart your ATPLs.
Which undoubtly will take a few months, meanwhile the period in which you will have to finish all of your ATPL exams will keep on ticking (max. 18 months counted from your first exam).
+ you'll have to find another groundschool (= paying again), which sucks if you've already paid your fees etc at the integrated school.
Some CAA's will even render your ATPL results invalid if you 'restart' your training program elsewhere, it is completely ridicilous but what can you do about it. Not all CAA's do this, so inform at your national CAA.
Have you already done some exams?