THE message from Nicola Sturgeon to the gung-ho within her party was a clear "simmer down". All 24 polls on the constitutional questions in the last year, she acknowledged, had shown support for independence higher than it was on referendum day but in the First Minister's opinion at least, there remains a way to go before a repeat vote will be called.

As she issued her call for caution, hundreds of those it may have benefited most were not watching on TV. They were instead gathering just two miles away preparing to march on Holyrood to demand a second referendum by 2018. The event, according to its organiser Harry Samh, was designed to ramp up the pressure to go for independence well within the next Holyrood term.

"Polls are showing a majority would vote yes," he said. "Timing is key, it's got to be when the Tories are still in power. On social media, it's already starting to build up again, a lot of people who voted No are now Yes, they feel cheated."

Mr Samh said that police had told him between 600 and 700 people had been on the one mile march to Holyrood, a total that looked optimistic. But there were least 300 outside the Scottish Parliament, many of them SNP members, on a Friday morning. His theory that large numbers of No voters regret their decision last year was a popular one, but while everyone apparently knew a repentant ex-unionist, there were none to be found among the marchers.

The consensus seemed to be that 2018 was an ideal date for a second referendum, representing the dilemma facing the First Minister. Her party's ranks have swelled from 25,642 to 112,208 in the last 12 months, but with no major elections on the horizon after May to occupy her activists, keeping a lid on a clamour for a second referendum may become increasingly tricky.

Jim Oliphant, from Fife, turned up in a Saltire Guy Fawkes mask, a Jimmy hat and a striking pair of Scottish-themed beer bottle glasses which he had customised by writing 'vote SNP' on the St Andrew's Cross.

"I think Nicola Sturgeon has to include another referendum in the manifesto," he said. "Times are changing fast. Independence has never been more important. I think we need to give the Tories a couple more years to hang themselves. By 2018, Trident will have passed, so that will be a really good time."

Solidarity, the convicted perjurer and former socialist MSP Tommy Sheridan's party, was also visible. It has adopted a strategy of exploiting the desire for a new referendum by encouraging voters to back the SNP with their constituency vote, before lending it their backing on the list. It has promised that its MSPs, should it win any seats, would demand another referendum by 2018.

Richard McDade, from Broxburn, joined the SNP after the referendum and said it was mainly members of his party on the march, although he praised the "good work" of Solidarity and admitted there was a fierce debate over the right time for another vote.

Another newcomer to the party, Robbie Gallagher, said many were "desperate" for another referendum. "If you're a realist, you've got to strike while the iron's hot. You fight when you have the advantage, and David Cameron is the best person for us as Prime Minister. I don't care if it's two or three years, but we don't want independence to go on the backburner."

Even long-standing members of the SNP are finding the lure of a second referendum hard to resist. Malcolm Brown, who first joined in 1964 and has seen a transformation from a fringe organisation he says were once labelled "terrorists" to party of government, said: "My heart says let's do it tomorrow, my head says 2020 or 2021."

It is clear that only cold, hard calculation will drive the First Minster's decision on a second vote. The same, on yesterday's evidence, cannot be said for the more hot-headed among her party's grassroots.