The best honest reason to get back in touch
You already know these people. You interviewed them, placed them, or came close. What you lack is a reason to write that is not "just checking in", and a record that still tells the truth about where they work.
A promotion or a move gives you both. It is a real event in someone's working life, and a short note about it reads as attention rather than as a mailshot. It also repairs the record. The person your database calls a senior analyst at acme may have been running a team somewhere else for two years, and every search that touches that record is wrong until someone corrects it.
By hand, this means opening profiles one at a time, so it only ever happens for a handful of favourites. The play does it for a whole segment, in batches.
What you get back
A table of the people in your segment with a detected change: what your record says, what was found, whether it is a promotion or a change of employer, and the date of the event where the source gives one. Beside it sit the proposed record updates, waiting for your approval, and a draft message for each person you chose to write to, staged and unsent. Everyone else is listed too, split into checked with no change and not matched, so you can tell the two apart.
Variations worth knowing
Promoted into a hiring role. A candidate who becomes a head of department is a buyer. They are listed separately, because the conversation and the channel differ. The client-side play is follow your client contacts when they move company, which uses work email and qualifies the employer first.
Start with the people you placed. A placed candidate who has since left has emptied a seat at a client you already work with. That is worth knowing before the client mentions it.
Re-read the profile for the people who matter most. For a short list of high-value candidates, the agent can pull the full dated work history instead. It is a paid lookup per person, and a change shows up as a difference against your record even where no event was reported.
Where this goes wrong
Reading no match as no change. A signal provider only knows about the people it can match to its own records. A candidate it cannot find comes back with nothing, and nothing is not proof that they are still where you left them.
Pitching a job inside a congratulation. Someone who has just been promoted or has just moved is cold for a role. Write to reconnect, and leave the vacancy for the conversation that follows.
Checking the whole database. Matching and checking are charged per person. A full database checked blind is an expensive way to learn that most of it was never worth a message, and thin records often fail to match at all.
