A champion who changed jobs is a buyer who already knows your product works, already knows how to sell it internally, and has just arrived somewhere with a budget and a mandate to fix things. They are not a lead. They are a customer who happens to be at a new address.
Two things make the window narrow. New executives make their tooling decisions in the first few months, and after that the budget is committed. And your champion's goodwill fades: six months in, you are a vendor they used to use.
Wider than most teams build it:
UserGems does this one thing and does it well: it watches your CRM contacts and alerts you when one moves. The right answer if job changes are the only signal you want.
Relationship intelligence picks it up as part of mapping the graph. Orbb tracks where people in your network go, so a champion's move arrives beside the other warm paths into that new account rather than in its own silo.
LinkedIn Sales Navigator has a saved-search alert for job changes in a lead list. Free if you already pay for it, manual to maintain, and only as good as the list you remembered to build.
Not a pitch. The move is the reason to write, and the note should read like one person congratulating another:
The meeting comes from the second message, and only because the first one was not a pitch.
Tag these opportunities at creation. Champion-move pipeline behaves differently from cold and from inbound - shorter cycles, higher win rates - and if it is not tagged you will never be able to argue for the headcount to work it properly.