That "agreement"

The Times reports:

The most serious stumbling blocks to an orderly Brexit may in fact be those the negotiating teams are already struggling with. Britain’s insistence on leaving the jurisdiction of the ECJ in its entirety has left unanswered the question of what is to replace it when London and Brussels disagree on matters of mutual commercial interest. The European Commission says it awaits a British proposal. On the Irish border, Brussels’ language on full regulatory alignment for Northern Ireland and the Republic remains in the transition deal as a “backstop” even though Mrs May has called it a scenario to which no British prime minister could agree. Even so, her negotiators are engaging in this vital debate on the EU’s terms. Amid justified optimism, two big cans have been kicked down the road. If they are not clanging loudly, it is because they are still full of fudge.

Throw in the fact that there is no provision for any possible extension of the transition period and I am far from sure that any optimism is justified.