From: DMcG - PM
Date: 15 Nov 17 - 04:43 AM
Well, here is one scenario. Suppose absolutely everything is agreed by that date except one item of significance - for instance some aspect of the Northern Ireland border. Let's also assume both sides are confident it can be settled with a further two weeks of discussion.
Does it make sense to say we have reached an arbitrary point in time, so we will throw out everything we have agreed to go with something we both think is worse?

If they can get everything else sorted within the timescale, I can hardly believe that a final matter should take another two weeks. By giving a definitive timescale they have to work to have everything completed. Otherwise it may become 'another two weeks' which becomes another month . . .