While the other answers are good, I like to take a different approach to performance reviews. This situation used to happen all the time when I was in the military. Performance review time would be up, and boom, supervisor is on remote temporary duty for 6 months or you get assigned a new supervisor because of an organizational restructure (happens all the time). The only constant in the entire process is you, so you are the only one who can be depended upon to make sure that your review is conducted properly, fairly and timely.
I've said this in other postings, but I'll never get tired of saying it. You should always keep an "I love me" folder somewhere. I prefer a hard copy file most of the time, but in my current consultant role I've transferred my file to digital and uploaded it to a shared drive so I can get to it anywhere/anytime. In this folder should be emails, memoranda, and recorded metrics about all of the good stuff you've done. This should include any benchmarks on projects, deliveries, anything you would put on a resume or on a project completion report.
Keep track of the stuff that you haven't done well with as well, but include this as more of a personal improvement plan. Identify problems you had with projects, places you feel improvements can be made. Include a plan for making those improvements. Provide citations for when you sought feedback and assistance.
In a nutshell, you want to be able to provide this folder to your new supervisor in a meeting to identify all the good things you've done, the places you feel can be improved and anything that shows you are a team worker and asset to the organization. Coming to your performance review prepared in this fashion will only impress your supervisor more.
In the next two days I would suggest you use some time to track down every bit of this kind of information that you can and prepare at least a hurried version of such a folder.