Whether there is an official plan or not, I'm sure that all sorts of alternatives have been discussed by American & other conservatives along with the primates of the Global South. Why should the Guardian be surprised at this?
What this article is NOT doing, though, is presenting the situation as it will really be if such a split occurs-- the conservative parts of the American & other embattled churches will align with the rest of the Anglican communion, leaving the liberal ECUSA & other liberal national groups marooned as splinter islands apart from the main. It will be VERY clear where majority opinion lies, something that hasn't been at all clear so far.
Maybe not a complete answer, but see post #5.