Just had this happen to me. Now I've got to parse through 18,400 names - not a happy camper! Please add some type of global selection to this list.
Edit: Restored the DB from a backup - only 3 people to add back. FWIW: I used the "collecting changes" feature multiple times yesterday - moving data to and from Ancestry and I did not experience this problem. However, this morning after adding a 3rd person to RM everyone in my RM DB was tagged as changed. Ugh!
Even more fun when you have a database 2 1/2 times larger!