It's early morning here in Brussels and everyone is waking up after a late night, starting to sift through what really happened at David Cameron's "make or break" dinner, Peter Foster, our Europe Editor reports. The Prime Minister claimed immediately after last night's dinner that "four years" was still on the table, but the question now is in what form, exactly? The devil will be in the detail. Mr Cameron began this "showdown" summit saying he wanted the right to discriminate against non-British EU workers receiving in-work benefits, but even before the dinner started, the demand had been unanimously rejected as impossible. As the leaders made their arrival yesterday evening, there was a common answer to the question of whether Britain would make EU workers wait for years - "no". It was a diplomatic mugging. But hours later, all the leaders emerged from their dinner of roast venison talking about consensus and a determination to reach a deal in February that took into account Mr Cameron's concerns - expressed in heartfelt terms during his 40 minute speech - about the pressure caused by migration. Given the unanimous clarity of the other 27 EU leaders that Mr Cameron's "four year" benefit demand was impossible, the post-dinner optimism can only be explained if one side showed considerable new flexibility on the issue. And it seems clear that on this core issue, it wasn't the other 27. More details will emerge today, but it is pretty clear that Mr Cameron has dropped his discriminatory four-year demand, in exchange for help on migration - perhaps an "emergency brake" on some other headline-grabbing idea to recognise the UK's position. Add to that some additional "red card" type scheme to give national parliaments greater powers to check the Brussels executive and a clear statement of a multi-direction Europe (end of "ever closer union") and Mr Cameron may just about have himself a saleable deal.