You are obligated to the old leases until they terminate. If over a year has past in most cases the tenant will be month 2 month (check your lease and laws).
If M2M, just give them 30 day notice and say bye-bye. If they don't move you file papers and start eviction immediately on the 1st of the next month. On a holdover tenant you don't need to post any 3 days or whatever, you just serve the Summons to court.