Short answer: yes.
Long answer: you can write scripts and stuff to do that but not all of the processes follow the same annotation for their elements and methodology of them are not the same as well as their parameters. So it's easy enough to automatize the schematic transfer but you're going to have to run all your simulations and stuff.
Additional answer: Some processes can be scaled down, for example 65nm can be scaled down to 55nm, in that case migration is basically doing nothing.
Additional additional answer: Since after designing the circuit in 0.25um you will have a lot of experience designing these stuff and their relations, you wouldn't have that much of a problem designing a new one. Also you should keep all your testbenches and create generic testbenches and stuff.