EllieandCraig: Theyre saying weve used over 4000kwh in a qtr?
I see you previously had trouble understanding your bills so I'll try to be helpful.
Unless your meter is reading wrongly, which is extremely unlikely, the current meter reading is the current meter reading. 4000kWhrs of gas in the winter quarter is not exceptional. Whether it's actually 4000 (or 3500 or 4500) depends on whether there were actual readings or not at the start and end of the quarter.
If you are interested in understanding your consumption take regular readings. Daily at first, then weekly and finally monthly when you begin to understand your consumption patterns. Whenever you get a bill, if it is based on an estimate, you are entitled to provide a customer read and have the bill re-issued. Up to you but I would always recommend that.
It's early days in your BG supply for a consumption pattern to have emerged. Probably the £3 reduction was a result of the BG price reductions, a debit of £93 is not massive following the winter quarter except you haven't said what your monthly gas DD is. It might not actually be a £93 debit if the bill was issued a few days before the monthly DD collection.
The next quarter's bill will be a better guide. I wouldn't worry based on what you have said.