It might have been previous advice but not now.
https://personal.help.royalmail.com/app/answers/detail/a_id/5317/~/international-incident-bulletin
"Last updated: Tuesday 29 December 2020
Welcome to our international incident bulletin; a round up of any issues which may be affecting mail services to and from countries around the world.
We keep this information as up-to-date as possible, with information supplied to Royal Mail by the various foreign national postal authorities.
Coronavirus Impact
Royal Mail and Parcelforce services to Europe have been reopened and are now fully operational. For items posted today, customers should expect a delay up to 2 working days for some countries.
We're working with our airline and postal/courier partners across the globe to maintain services, however delays should be expected. Many countries have implemented special measure to combat the spread of Coronavirus COVID-19, especially for signature service to maintain social distancing. The number of countries we can access is changing daily.
We strongly advise not to send items to destinations listed as ‘On suspension’."
Portugal is not suspended