“We aim to deliver at least every other day in these areas, though this may not always be possible in offices temporarily affected by very high levels of absence.
“We’re sorry for any inconvenience and thank you for your understanding.”
Royal Mail added coronavirus vaccine letters and test kits remains a priority.
“We’re working hard to deliver as comprehensive a service as possible with the resources available to support these offices. And we’re ensuring we prioritise delivery of Covid-19 vaccination letters and test kits.”