ATPL theory credits expire and people still borrow money for modular courses. The OP says he has the cash to pay for an integrated course so hopefully debt should not be a problem for him. Whether or not it is a good or bad decision personally is another issue, only the OP can decide that. You say modular is safer because you can pay as you go, if the OP has earned the money already, then that is irrelevant as he should have still budgeted accordingly. If he has the money to leave work to train, then lucky him.
I realise the 'mindless' comment was not aimed at me, but I did feel 'little wonder you seem to have been so easily sold by CTC' was. Don't worry, I won't bear a grudge! Right, bed time!