What's the procedure on changing health insurance companies?

I have health insurance but want to change to get onto my husband's insurance (military) and cancel the plan I have now. Should I let the insurances overlap (apply for one while I still have the other) or should I cancel my current one before I sign up for my husband's?
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I would be safe and let them overlap. I do Medical ins. billing and you would be caught off balance if you did not overlap them. Very few people really know what all the ins. co. make it hard to coordinate policies (they make money). It is going to be to the advantage of yourself to have double coverage. Once you have a Ins. card in your hand from the Military (champus Ins?) or a letter of confirmation, then canc. your primary. I hope this helps...
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