Medicare claims often take 2 months or longer to filter through the process. If your plan is to change plans/carriers every 2 months or so you will really have no idea whether you are doing the right thing or not.
Providers have up to 12 months from the date of service to file claims. Once filed, the adjudication process often takes a month for routine claims, longer if complex.
LD - is there anything Bob should add for clarity? Unless, of course, he sent it to you for proofreading (which would only be prudent).