This is due to RM's new machin barcoded NVI and normal stamps which are in circulation.
NOTE: Machin and Definitives are the same
All is not lost.
From 31st March 2022 you will be able to swap unused non-barcoded Definitives (Machins) and NVIs with new barcoded stamps.
These are not affected by these changes, so those of you who use special stamps as postage stamps will still be able to do so after January 2023. They will not be part of the Swap Out scheme.
NVI Christmas stamps are being barcoded starting this year.
However, in a change of plan Royal Mail has announced that old, non-barcoded NVI Christmas stamps will remain valid after January 2023.
All PPS, since their inception, will be valid after January 2023.
You will need a Swap Out form to exchange your unused non-barcoded stamps. These will be available from 31st March at Customer Service Points, the Royal Mail website and from Royal Mail’s Customer Experience team.
Swap Out forms will NOT be available from Post Offices.