Renaming the file will only address part of the symptoms and will leave incorrect metadata in the original files. The internal shoot date present in the RAW file (I assume you have been shooting RAW files? anyway, the same would apply to JPEG files) will still display the wrong date. This could lead to confusion should you ever process the files outside of Lightroom.
One alternative approach would be to use
exiftool to batch modify all dates for all files in a given folder. In your case, the following command would perform a shift of +1 year for all dates in files present in the current folder:
exiftool "-AllDates+=1:0:0 0:0:0" -verbose *.CR2Note: replace the .CR2 extension in the example above with whatever file format you are dealing with.
You would then have to reimport the modified files in your Lightroom catalogue to have the correct dates set on import.
Disclaimer one: care should be applied when editing RAW or JPEG files with an external editor. Work on a copy of your files and ensure the processed files can be imported in Lightroom and worked on normally before discarding the original files. I have never encountered problems doing the action above, but you are doing this at your own risk!
Disclaimer two: I have been doing this on a PC, however it should also work on a Mac with the appropriate version of exiftool. The syntax of the command above might have to be changed slightly.
Cheers,
Fabien