Ask HN: What to do next after landing a PT contract job?

This job came unexpectedly. I just replied to a job listing, interview was very informal (text chat, not even over the phone) but my past experience and projects were pretty good and convinced the employer to produce a contract and hire me part-time work (15-20 hrs). They have funds for at least 4 months which would be at least how long this contract will be for.

I'm a programmer and was looking mainly for full-time work but the experience this job would provide is something I really wanted, which is why I took it. So it's a different turn of events for me.

However it's also part time and I am not one of those "expert freelancers" that can turn up clients consistently. I have 20-25 extra daytime hours out of a week to do other things.

So what would do with this time? Should I try to go for another part time job? They are, however, uncommon for programming. Or jump right into freelancing and try to push for similar jobs at better rates? As long as I have this contract, I feel I have more leverage to pass on less desirable clients.