FMLA-efployee return to work same office, how soon canemployer let go?

FMLA Question
1. When an employee returns to work before expiration of FMLA period, can the employer state that the only available position is at a different office 3 1/2 hours away?

2. What would be reasonable in terms of a time-frame if the employee returned to work and the employer then let the person go (dismissed/laid off-but not as part of a RIF with others)?

Thank you
Note-I am an employee