Taking bookings from customers within lockdown areas?

The restrictions essentially mean people should not enter or leave the Caerphilly County Borough area. A post code checker is available here to ascertain which addresses fall within the area. Welsh Government guidance has been published here which includes that any plans to travel to a second home or for a holiday should be cancelled.
 
The guidance does not advise Caerphilly residents already away to curtail their holiday but says ‘people who left the Caerphilly County Borough area shortly before restrictions were put in place should be aware they pose a higher risk of transmitting the virus, and so ideally they should return home as soon as possible’.
 
Visit Wales guidance – https://content.govdelivery.com/accounts/UKWALES/bulletins/29f2756 - explains that the obligation to comply with the restrictions rests with the individual (for example the Caerphilly resident), rather than the business saying, ‘There will be no legal obligation for accommodation providers outside an area where travel restrictions are in place to check whether guests are resident within that area, or to enforce the law by turning people from that area away. They should not, however, knowingly accommodate people who are acting in breach of the law.’ However it does state, the Guidance therefore suggests ‘Accommodation providers may wish to communicate to all customers with existing bookings, reminding them of the law and giving them a chance to cancel or postpone their bookings’.