I know strange thing to worry about...

I have an old grid and a new grid.

clientA has been on the old grid for years backing up just fine.

     last backup on old grid was 1 tb with 2.6% on New Bytes

clientA was retired from old grid

software upgraded on client to match new grid and registered to new grid.

     first backup on new grid was 1 tb with 20% New Bytes

That New Bytes is "new to Avamar"?  and not the client?

Just wanting to make sure that the Client is getting all the data to the new grid, and not skipping anything because it sees it in its f_cache.dat file and thinking it has already sent it.

wondering if I should be removing the f_cache files on the clients when I register them to the new grid.

(Just me being paranoid)