Stephen,
Welcome to the wonderful world of professional certification where certification maintenance can often creep up on you quickly!
As Elizabeth said, yes it is possible, but you have toe be deliberate about it. There are courses, webinars and books that will all count towards certification maintenance. But be careful, PMI CM also requires 8 minimum hours in each of three pillar areas of "technical," "leadership," and "strategic/business.."
OSP, the creators of the PrepCast also has both a subscription and free podcast service. The subscription service will hit the required areas easily, while the free service requires some deconvolution to assign areas.
Good luck!
Harry
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Harry J. Elston, Ph.D., CIH, PMP