Well, I'm sure that the first preference for the EU would clearly be to get what it wants, but it will be at least tempered by a desire (on both sides!) not to drag the thing out indefinitely.
That, incidentally, is the great lie about Brexit supporters who hated this deal and the backstop. There are plenty of things wrong with the deal, and I cannot support it, but the idea that it would lead to the UK being trapped inside the backstop forever was not one of them. It would suit nobody to have the situation never resolved.
Not, I hasten to add, that I supported this deal. But I fear that some Brexit supporters are too wedded to the idea that the EU is an adversary to be willing to ever compromise.
So, in that sense, yes, there appear to be only two achievable outcomes left.