They did .
Here , from Wiki
Following open tender under EU public procurement rules in 2018, the Franco-Dutch security firm Gemalto was selected over British banknote and travel document printer De La Rue. The result of the tender proved highly controversial, as it saw the production of British passport blanks moved from Gateshead in the UK to Tczew, Poland
https://en.wikipedia.org/wiki/British_passport#:~:text=The result of the tender,it being more cost efficient.