Start as early as you can. Energy costs tend to rise year on year, and geopolitics can move a market overnight. Waiting leaves you buying whatever is left.
We can tender up to 36 months before the current contract ends. That is how you lock a rate before the next lift, not after it.
Once we have the meter information, a full group tender is usually back in one to three days. We still read the bills first. We will not go to market on a volume we have not checked.
The expensive outcome is not a slightly worse unit rate. It is rolling onto out-of-contract rates because the termination window closed while someone was on leave. That is why we keep a diary after you sign, and why we ask for the end date on the first call.
Contracts themselves run 12 to 60 months. The lead time is about when you go to market, not the term you pick. Short if you want to stay close to the market. Longer if the curve is paying you to lock. We will say which is which.