Legal Question in Landlord & Tenant Law in Georgia

Have you read your lease, beyond the date it ends? We don't have it. Do you know the notice requirements, the terms of the security deposit, how the deposit is accounted for, etc.? It will almost always answer your questions and, no, virtually all leases expressly prohibit what you propose. It would make no sense at all for a landlord to get a security deposit, only to use it for the last month's rent and have nothing for possible damages after move-out. If a security deposit was a"advance rent" your lease will say so. Read it.

I'll add that as far as fulfilling all terms of the lease, no, the landlord cannot force you to enter into a new term or month-to-month, as long as you fulfill all terms (rent, notice, etc.) of the current lease. You will likely find that you are much better off fulfilling the terms of the lease, even if you don't live there the last few weeks. What you propose is early termination (another provision that is likely discussed in your lease).