Every new practice is protected by someone. The question that decides its survival is what happens when that someone leaves.
Sponsor air cover is the most valuable and least durable asset a new initiative has. It buys time against the parent organisation's metrics — right up until the sponsor is promoted, reorganised, or gone.
The practices that survive the handover are the ones that used the protected window to manufacture their own evidence: a paying client, a defensible margin, a story the next sponsor can adopt without having to believe in it on faith.
Before the sponsor leaves, make sure you have
External proof. At least one client outside the parent who has paid for the work.
A portable narrative. A case that the next sponsor can champion without re-litigating the original decision.