Quite right! When I travelled from London to Lille (France) on Eurostar three weeks ago, my passport was stamped by the French with the simple explanation that France does not recognise the ‘temporary’ Portuguese document as valid for entry to the EU.
At least I shall be travelling from France to Portugal direct in a few days, so no controls, but then I shall have to make sure my passport is stamped upon leaving Portugal at the end of September for a short trip back to UK. But supposing I wasn’t?
A friend, with Portuguese residence, now living in Denmark, has the same problem. Denmark also does not accept the temporary SEF paperwork. She had her passport stamped going from UK to Denmark and is now in limbo. Advice is to keep all travel tickets, boarding passes etc as proof of crossing the EU border.
I have not, nor have any of the 40 or 50 people I know with residence prior to January 2021, had any contact from SEF regarding new documents.
A pity that those who campaigned so vigorously for UK to leave the EU did not explain these consequences.
And leaving the EU is not ‘keeping foreigners out’. All you need is either to be a footballer or have a rubber boat on Calais beach (not a politically correct point of view but what many people I know do really think!)