BTL tell me that they will shortly be changing their admin system. At present a human (in Belize City) makes the decision to pull someone's phone service. That will be automated so what little discretion they practice at present (none, I think) will disappear. They suggested (though did not state explicitly) that this auto-disconnect will happen immediately the due time for them to receive payment has passed. Contrast that with practice in the UK, where they use their system to send you a reminder, then in extremis cut you off for outgoing calls but leave incoming ones working. Then they actually phone you, person to person, to see what the problem is. Only after they've exhausted all reasonable avenues do they disconnect the line. Even then, it still works for emergency calls.
This isn't because the British telephone company is magnanimous and likes to give money away, but because they're regulated by government. Something that isn't likely to happen here any time soon.
As I said, a nice little earner.