May 1 is the first anniversary of Cancellation Day, our campaign to remind C-Store readers that they need to tell their gas and electricity supplier that they don't want to continue their current contract.

Last year we revealed how thousands of convenience retailers had been rolled over onto far higher tariffs and tied into long-term contracts because they missed the deadline for giving notice of termination of their contract.

One simple letter, we said, could save your business thousands of pounds a year and from the response we received from readers, we're confident that many of them made enormous savings as a result of our campaign. Now, a year on, they need to check their contract and prepare to renegotiate it again.

But the problem of 'rollovers' continues. We're still receiving calls from distraught businesses who have fallen into the suppliers' trap and are finding their bills have doubled or worse. So later this year we'll be back on the soap box, with a new date for Cancellation Day in November.