John, I ran AnyFilter and found most but not all files that needed updating. I've ran it several times and each time, I updated the masks and then ran AnyFilter again and found more. I'm a bit confused as to what's going on.
I've also noticed that there are some files that need the healing brush to be updated. Is there any way to find those?
I also have another situation where a couple of files were corrupted and could not be read by Lightroom in the Develop Mode. Those files had to be recovered from a backup. I know that you can find missing files in Lightroom itself but is there any way in AnyFilter where you can find a file that is present but can't be read by Lightroom. Or is that a leap too far?
[This post contains formatting and embedded images that don't appear in email. View the post in your Web browser.]
"I've also noticed that there are some files that need the healing brush to be updated. Is there any way to find those?"
Try this Any Filter query:

Copy and paste this line (as one line) into the "code:" field:
require "Util".arrayReduce (photo:getDevelopSettings ().RetouchAreas or {}, false, function (b, a) return b or (a.SpotType == "heal_patchmatch" and a.pm_patch == nil) end)
Update: I corrected the "code:" line above -- I had given an old incorrect version. (I'm adding this as a built-in filter in the next release.)