In order to keep your your JAA ATPL exams valid all you need to do is renew instrument rating (IR) every 7 years. I don't know if your CPL has to be valid all the time throughout the period, but renewing SEP and therefore CPL can be (I'm not saying it should be) done by one-hour flight every 2 years with an examiner.
Why don't you get a degree first and then do your flight hours when economy picks up?