Tanlou, sorry to hear of your troubles with that.
I once got an estimated bill for $24,000 or so, was obviously a mistake and easily sorted, but still took time to work through with phone calls.
It's hard to work out why the meter was allowed to continue as an estimated read for so long, unfathomable why an electrical retailer would allow it, just for the reason in your case (money sitting around not billed for).
Their estimated use reads might have been on a previous owner / tenant, a very frugal one, and over 2 - 3 years it would be easy for underestimated bills to accumulate a few thousand dollars of unbilled power.
AGL took a grand off the bill, suppose it shows some flexibility and reduce your pain a little.
Didn't you see 'estimated' reads on your bills ?
You must have an old analogue meter, which you could have (if you had access to the meter) done a manual read and inputted into the AGL app or website under your account.
IF the readings were accurate on the old meter removal *, then it will hurt for sure.
* I say this because I recently had a new smart meter put in when we went with solar, and my wife took a photo of the meter just before it was removed.
Our AGL download info shows AGL have registered 150kw MORE than the meter actually read to the final read.
Haven't got that bill yet but will be checking and taking that up with them, only $70 or so but it's more a principle thing.
The new smart meter will at least mean you never get an estimated bill.
Just watch out if your tariffs changed to TOU or such, and you are not used to this over perhaps a single tariff.
It can make bills much higher if you don't use power wisely.
All the best.
