I've just come across this on another expats forum and the document explaìns all aspects of the withdrawal agreements. It might clear up some misunderstandings.

https://www.gov.uk/government/publications/withdrawal-agreement-explainer-for-part-2-citizens-rights

Steve

https://assets.publishing.service.go...ni-from-eu.pdf

Para 28 - b : it's not clear if the "right to aggregate periods of insurance, employment, self-employment or residence completed, for the purposes of meeting different states’ benefit entitlement condition" applies if you have retired before the WA or will extend further. I have paid contributions for state pension in UK and 3 EU states but I haven't retired yet. Will I lose the right to aggregate these contribution the day I retire? I would have thought this was still under negotiation with the EU and it's not done deal yet.

Social security co-ordination is still on the agenda for the current negotiations, but I hear there are little outstanding issues compared to fishery and level playing field. We probably won't find out until agreement is concluded.