I will use my example - perhaps it will help you.
Just after my PPL(A) I attended ATPL(A) theory course - in fact it was distance learning course (app. 150h in class room, rest self-study at home). It enabled me to have full time non-aviation job + build hours in the meantime. After I passed all ATPL(A) theory exams I started practical part of training: CPL, ME, IR.
Remember that ATPL theory/exams covers area of CPL and IR. So it's better to do it just once.
Good luck
