I just started working for my job and their open enrollment for insurance is May 2015, can I buy coverage until I can sign up with work? Or once I sign up i am locked I for long term. Can I do a month by month term?
If you know you won't need your plan for the full year, simply get a Marketplace plan during open enrollment, then keep it until you don't need it anymore.
Make sure to cancel your coverage in enough time that your old and new coverage don't overlap, also make sure not to cancel it to early or you could face a coverage gap.