Re: "clarified once the uncertain situation caused by Brexit has been resolved"
I don't think so. I think the uncertainty over Brexit will be pretty much solved by June. I could be reading this wrong of course, but I just don't think there's going to be any large scale deal done at this point. Not until political leaderships have changed. Both sides have done too much to piss the other side off. The EU side couldn't resist continually prodding at May until they'd "won" the negotiation. Coming out with a deal that was so obviously one-sided that even if she could have got it through Parliament, a later government was almost bound to repudiate it. Plus they did their best to undermine her credibilty - only to act all surprised when she no longer had the political capital to push through the deal.
Also May was surprisingly careful in her language. Given some of the shit she took, particularly in some of the almost certainly made up leaks from quite a high level in the Commission - I was surprised she didn't hit back a bit more. And I think Johnson has taken some lessons from that (even if they're the wrong lessons), which are that trying to get a deal at any price (because you think no deal will be worse) means you'll be offered less. And also that not fighting the PR war means you get crucified in your own press and so lose the ability to govern anyway. Hence he's now going for the least ambitious agreement, in order to try and get something achieved.
The problem with fighting the PR war of course is that you're then giving the other side's politicians less room to compromise, because they also don't want to look weak in negotiations. But that's a game the EU definitely started deliberately with the supposed leaks about May "begging for a deal" and the demands for a €100 billion payment before they'd even start negotiations. Which was bound to poison the atmosphere - and now they're repeating the same mistake with all the rhetoric about how there can be no free trade agreement like they've offered to many other countries, because reasons. Even though the two sides aren't actually that far apart on some of the "level playing field" stuff - but they're destroying their own ability to compromise by being so strident before talks have even begun - while also making it harder for the other side to do so.
I think the EU have become obsessed with being seen to "win". Which is why we had three failed Greek bail-outs. And they made the Greek government grovel for the last one, in a completely unacceptable way. It's also what happened in the Cypriot bail-out. And I think Johnson has decided that it's not worth completely bending all his attention on getting a last minute deal a few days/weeks after the December deadline has passed. So he's going to walk away while it's still early enough in his government that he's got the political capital to be able to. And of course try and blame it on the EU. Then both sides will have too much political capital invested - so there'll be no new trade deal done until Macron, Merkel and Johnson are all retired.
A little noticed detail from Gove's statement to Parliament last week was what convinced me of this. He talked about setting a June deadline, after which if there was insufficient progress the government would concentrate of planning for there being no deal. The fact he set it as a deadline was pure trolling. Having a go at the EU for what they did to May with the timetabling of the exit talks and refusing to start until money had been sorted out, and then refusing to start talks on future trade until the withdrawal agreement was agreed - even though the Irish backstop would have been completely pointless if they'd been able to make a customs deal first. But I also think they mean it - because if you believe talks are going to fail anyway - then it's politically better that you control it - and can try to blame the other side on your own timetable.
I think there's a deal to be done, just nobody statesmanlike enough to get it. And to be fair to May - I thnk she genuinely believed that no-deal would be awful and that the EU wouldn't offer better - so it was her job to get what deal she could even if it destroyed her career and party. So I've a bit of sympathy with her. And even though I don't like Johnson, I think he's the negotiating partner the EU governments fucking deserve for the way they collectively behaved towards May.