Link to New National Restrictions from 5 November:
https://www.gov.uk/guidance/new-nati...rom-5-november
Not much detail on overnight or international travel other than this:
Overnight stays and holidays away from primary residences will not be allowed- including holidays in the UK and abroad. This includes staying in a second home, if you own one, or staying with anyone you do not live with or are in a support bubble with. There are specific exceptions, for example if you need to stay away from home (including in a second home) for work purposes.
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Developments in the coronavirus pandemic remain uncertain around the world. No travel is risk-free. If you do need to travel abroad before 2 December (and are legally permitted to do so, for example, because it is for work), even if you are returning to a place you’ve visited before, you should look at the rules in place at your destination, the Foreign, Commonwealth and Development Office (FCDO) travel advice and the current travel corridor list.