"dannyk, my recollection is that they may be paid but they won't necessarily rise with inflation as those of people who stay home do. I could be wrong about this."
Yes you could be jno. What you are talking about is the State pension. Ex-pats in certain countries (including, but not exclusively, all EU nations) receive the same increases as those living in the UK. For others their pension is frozen at the rate they received when they left the UK. List of countries which receive the increases is here:
https://www.gov.uk/government/publications/state-pensions-annual-increases-if-you-live-abroad
This latest scaremongering episode relates to private pensions paid by insurance companies and is quite clear is quite clear:
"Paying pensions cannot occur across borders beyond transition"
"Without a deal, insurers and pension providers would be legally barred from sending out payments, leaving policies dormant on their accounts."
And it does not effect only UK ex-Pats. There are 38 million people living in Europe outside Britain who have policies with U.K. insurers. All of them will be similarly prevented from receiving their payments should this utter drivel come true. Like I said earlier, I wonder how people originating from outside the EU mange to survive.