Panic stations?

Is there any point in Mrs May's last-minute dash to Brussels to meet Juncker and Barnier?  Mrs May and her colleagues do not appear to have an agreed position on:

1.  the amount they are willing to pay as the divorce bill;
2.  how to achieve a satisfactory outcome on the Northern Ireland border question;
3.  what residency rights they are prepared to grant EU citizens remaining in the UK;
4.  the length of a transition period after 2019 and the extent of ECJ supervision during that period (and, arguably, the need for a transitional period at all); and
5. what kind of trading relationship the UK should have with the EU after Brexit.

Nor can they be sure that any answers on any of these issues will be acceptable to the House of Commons.

So what is Mrs May going to do in Brussels?  Juncker and Barnier are constrained by their terms of reference which prohibit any advance on trade negotiations until sufficient progress has been made on the first three points listed above.  And I fail to see how May and Davis can offer any solutions on those points.