FBBRENUM will renumber your messages, starting from a value which you specify. The new starting number may be either higher or lower than the existing value. However the normal use would be to 'reset' the numbers to lower values.

The program updates DIRMES.SYS so that XFBB recognises the new numbers, it also makes changes to INF.SYS so that users can continue to use the 'L' command exactly as they did before the renumbering (each users ON base value and Last Message values are adjusted), and to WFBID.SYS so that the MID/BID History shown by the sysop 'FI' command remain valid.

Note: All my XFBB programs are provided as-is, I have not used them for over 10 years and have no way to test them, I am able to provide very limited support in trying to use them.