Timing can be everything. And as the days tick down to a likely deal with the rest of the EU, ministers' minds are turning to what happens as soon as the ink is dry, or more like the complicated agreements are run off the printers in the European Council.
I'm told the prime minister is being urged to hold an emergency cabinet as soon as the crucial EU summit in Brussels concludes and he can get back to London.
Some cabinet ministers fear that if, as expected, David Cameron concludes the deal with the rest of the EU on Friday 19 February, that the cabinet will not meet until Tuesday to decide formally the government's position.
That would give the prime minister, and those fighting to stay in the EU, a head start in the vital early days of what's likely to be a short campaign.
And some even believe the issue is of such importance that House of Commons could even be recalled over that weekend to debate the likely deal.
The deal is far from being concluded, but politicians are lining up to express confidence it can be done next month.
Several cabinet ministers therefore believe that David Cameron must guarantee that the cabinet will meet as soon as he returns from Brussels on the Friday.
One told the BBC it is "inconceivable" that the prime minister would be able to make the case for his deal before meeting senior colleagues, some of whom are likely to campaign for Out.
Another senior Conservative said that it would be "right and proper" for the cabinet to meet on the Friday.
A No 10 source said the focus was on reaching a deal, rather than what happens afterwards. But the concerns over choreography are real, a symbol of how much is at stake.