What are Denmark's special travel restrictions on the UK?

From June 11th, special travel restrictions were imposed on those travelling from the UK, which is currently ranked "orange" in Denmark's traffic light system, with four "red" regions where the delta variant is particularly prominent -- Bedford, Blackburn with Darwen, Bolton and Rossendale. 

There were extended on June 26th. 

What are the ordinary restrictions on travelling from the UK (and all other "orange" countries). 

Travellers who are permanent residents of the UK and not Danish citizens, and who have not been vaccinated or recovered from a documented Covid-19 infection in the last eight months, need to have a "worthy purpose" to travel to Denmark.

These include business trips, study trips, and visits to close family. Here is the full list of worthy purposes (stroll down to the bottom of the page).

All travellers coming from the UK who are not vaccinated or immune (regardless of where they are permanent residents) also need to show a negative coronavirus test less than 48 hours old at the time of boarding. (Vaccinated or immune people need to show proof of this). 

You need to get a quick test (antigen test) at the airport (these are free, and can be taken between leaving the plane and arriving at border control). Again, you are excused this if you are vaccinated or immune (with some exceptions in the next section).  

You need to isolate for ten days on arrival in Denmark. You may stop self-isolating after obtaining a negative PCR test taken no earlier than on the fourth day after entry.

What are the special restrictions currently imposed on the UK? 

Unlike travellers from normal "orange" countries, travellers from the UK must show a negative PCR test before boarding the plane to Denmark. 

Even those who are only resident in the UK, but travelling from another country must show a negative PCR test less than 48 hours old before entering Denmark. 

What are the special restrictions imposed on those who are resident in or have recently visited one of the four "red" areas? 

Even those who are fully vaccinated and have visited or are resident in one of the four "red" UK districts need to isolate on arrival in Denmark.  

Even those who are fully vaccinated need to show a negative PCR test less than 48 hours old before boarding their plane. 

What are the restrictions for Danish people in the UK travelling to the four "red" districts? 

Danish citizens and residents are advised not to visit Bedford, Blackburn with Darwen, Bolton and Rossendale, even for business travel. 

Be warned: it seems some airlines are interpreting the special restrictions in their own way. 

According to Rebecca, a reader of The Local from Southampton, British Airways has been insisting on all passengers showing a negative PCR or rapid test before boarding, even if they are fully vaccinated. 

Passengers who have travelled to Denmark with Ryanair, however, report that the airline does not require those who can document a completed vaccination to also show a negative test result.