Changing the encryption key on a file??

Can I change the encryption key on a file?? Imagining that I start my repository with only a single key, and then I add another key. If change the filter and diff values on an already-encrypted file, will git-crypt de-crypt and re-crypt that file with the new key?

This tool is one of the most fantastic products I've seen in a long time. Simple, easy-to-set-up, and very effective. Thank you!