My previous property was a flat in Glasgow which we own and is now rented out. Our provider was Scottish power at that time and my wife was the account holder. We have not been issued a final bill from them as yet and haven't kept any previous bills.
I would follow everything that you say to the utility company up in writing.
They will of course try to rely on an estimated bill and you are entitled to dispute it on the basis that as you have said, you don’t live in the property very often for 3 weeks out of 4. In fact, you could not well not have been living in the property during this time.
If you get a bill which you think is unreasonable then dispute it with the complaints department and if they were not make the bill of an amount to your reasonable satisfaction based upon what I’m about to tell you to do, then simply make a complaint to OFGEM.
You are going to need something in support of your complaint which you make initially to the utility company and if that fails, to the Ombudsman.
To support your complaint you need to monitor your amount of electricity usage on the meter over the period when you are away compared to the period when you are at home.
That needs to be in respect of the same type of season to take account of weather.
Can I clarify anything for you?
All makes sense. Thank you for your response