1. The government accesses the Meter Point Administration Number database held by UK Energy Networks. This lists every meter in the UK, along with the associated DNO and supplier registered to the MPAN.
2. It's not a payment, it's a supplier-applied discount. Not actual cash coming from the government. Paid for by the increase in everyone's standing charges to the tune of £20 a year. Unless you get the Guaranteed Credit Element of Pension Credit, which is the only AUTOMATIC way of getting the discount, you are in the 'Broader group' who also need to qualify by having a High heat cost home. Just because the DWP say you are eligible on the grounds of benefits does not guarantee that you will get the discount unless the VOA also verify you have a qualifying property. It's complicated, but that's how it is. If you live in a modern, well insulated home on mains gas, you likely won't qualify on the High heat cost, so may not get the discount. On the other hand, if you live off the gas grid in a 19c 'stone and slate' with solid walls and no damp proof course, it is likely you will.
The AFP is a completely unrelated issue. A one off. Too late to pay for the last lot of oil/coal/Calor that you may have already bought but if the AFP didn't exist you would have had to pay for your order anyway. Now this IS a taxpayer funded payment, in actual cash money, so when you think you ought to get it is a matter for debate, but it's up to HMG. It'll be in the pot by the time I next need to order oil, hopefully. They have said first week of Feb, alongside the Feb EBSS payment.
By the way anyone living in Wales on any kind of benefit, means tested or otherwise, don't forget to apply to your local authority before 28/2/23 for your Winter Fuel Assistance if you haven't already done so. I only realised I was eligible today when the council phoned me up and asked why I hadn't applied yet. £200 cash in the bank is not to be sniffed at. An hour after I applied, I had the text confirming this will be credited to my bank account within ten working days. You must be the lead name on your council tax bill and you must be responsible for your energy bills at your property, and only one application per household.