If a tenant's lease is up and they don't tell the landlord they are leaving until right before I think the only practical recourse would be withholding security deposit, but these days that happens so often for little to no reason at all it's unclear that would be any different.

As to raising rent at the end of lease, technically 30 days notice is required but I certainly have been in situations where landlords regularly did not honor this. You could push back and best case get a month of cheaper rent but at the risk it just turning into a notice to quite. But ultimately it comes down to weather or not you want to stay and the cost and hastle of moving even with 30 days is significant.

I would much prefer ops situation of being told 4 mo ahead what the new terms will be.