Will my surgery bill be covered by Medicaid if I just started a new job?

Who covers the medical expense depends on the policy that was in force on the date the service is provided. It doesn't depend on when the bill is generated, or when the the provider is paid.

For a simple expense such as a office visit, it is easy to pinpoint the date of service. For more complex things the expenses could be spread over several days or even weeks. There can be pre-operation expenses, and post-operation expenses such as stitches removal and physical therapy.

Everything that takes place while Medicaid was the insurer will be addressed by them. The question is what expenses will still be covered by them after the end date. I know that sometimes an office visit or two is covered as part of the surgical service.

You will also have to determine when is the first date of coverage for the new policy. Some start on the first day of work, others start on the first day of the next month. The new employer should be able to answer the question regarding the start of coverage. You might also have to talk to the new company to see what they will cover. Even though the law says they have to cover preexisting condition they still might be confused by physical therapy with no diagnoses.

You also might find that the new insurance company uses different providers. So they may require you to switch mid-recovery to get full coverage.