Hi,
Our meter is on 4575 today. I'm sure that the April reading was right, and given that it was so close to BG's estimate, I don't think the bill would have been wrong. if it was wrong, then surely BG would have contacted me? They are claiming that all the gas has been used between April and June. We also had problems with the boiler around January time I think, so it was out of action for a while.
Kim