The only well-known ISP that implements different customer pricing depending on exchange Market Classification is Plusnet. Note that for LLU ISPs, or at least their LLU products. Market Classification is irrelevant. It doesn't affect those in the slightest.
It's Orange's statement: "Like all of the major providers, we have to pass on the costs we pay BT to offer broadband outside our network area," that was confirmed by a member of their sales team as £10 when I called, which I find bewildering.
In the middle of replying I think I realised what is confusing you.
Let's forget LLU.
Non LLU ISPs get charged less in M3 that in M1. I'm not sure in M2, off the top of my head. I'd have to search around, and I'm ready for sleep

.
Plusnet charge £6.50 more in M1 than the do in M2 and M2. You are correct in thinking that they used to charge that extra in M2 as well. I seem to remember it was a lower premium, but maybe it was £6.50. Again, it's sleep time.
So the difference between Orange and PN is that wherever Orange did not have LLU, which means all M1 and some M2, they charge a £10 premium. PN only charge a premium in M1, and it is £6.50.
So far as I know all other ISPs charge a uniform price independent of market classification. One hopes that the price is somewhere between the two prices they would charge if they did do differential pricing.
The Orange FAQ should simply be changed to define the area correctly. The unfortunate sales person has to adhere to the company line, probably not even knowing it isn't any longer correctly worded. They don't have a network, so they can't have a network area. They aren't even technically an ISP. They are a Virtual ISP just like UKFSN, just rather a lot bigger.
Phew

. Not easy to work out when nodding off.
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