Thanks to information that has been shared with me by persons whose identities I should probably protect, I am personally convinced that Bishop Lamb's invitation to Lambeth is authentic, that it was issued with Archbishop Williams' knowledge and consent, and--do not underestimate this last detail--specifically at the request of the Presiding Bishop. I am not surprised by this, though I am annoyed because I believe the office that Bishop Lamb holds is of dubious canonical foundation. But I don't expect Lambeth Palace to have the resources to keep up with all the ways that due process and good order have been trampled in the "left behind" Diocese of San Joaquin.
However, I am equally persuaded that Bishop Schofield's invitation will not be rescinded, and that the only thing that might keep him from Lambeth is his health, which is ever on the edge of precariousness.
As many have noted, this creates a situation that is, to say the least, interesting. Under what titles will Lamb and Schofield be listed in conference documents? Presumably, only of one them, if either, will be directed to the queue that leads to an exchange of pleasantries with Her Majesty, sparing the Lord Chamberlain--or whoever handles such things--the awkwardness of introducing two purple-cassocked gentlemen as "the Bishop of San Joaquin."
My guess is that, in true Anglican fashion--that is, with decisions being made by indecision--we are witnessing the first step in the legitimation of multiple Anglican jurisdictions occupying the same geographic area. There will be more.