The first call
Who else is worth having on the call
For: Champion
A decision like this usually involves three to five people. Having one or two of them on the first call saves you repeating it, and saves them hearing it secondhand.
Worth considering:
Nobody needs to prepare anything. If it's only you this time, that's fine too.
To brief them first, send them Questions your team will ask.
Next: What we'll cover on the call