This has to be one of the top things to think about before embarking on a modular course, 'Will I finish it within time?'
I found myself in the same position, you think you have loads of time after perhaps suprisingly passing the ATPL exams first go, but then weather, money and various factors conspire against you, courses drag out, things take longer than expected. I had the CPL test passed and then started the IR on a part time basis because I had to work (couldn't get more leave after the CPL course even though I had the money). Through the IR training the ATPL exam passes expiry date loomed large and began to affect my concentration, I eventually realised that I was not going to finish the IR training (let alone the test), so I let it go. I just couldn't face doing the ATPL exams again, with the repeat expense, another 2 week brush up course, time off etc.
I made sure I got the Blue CPL licence issued, though without an IR its a bit of a chocolate teapot !