It was the same day Stansted went from 05/23 to 04/22. Still get it wrong sometimes....

Read somewhere that with the recent acceleration in the rate of change of magnetic variation, by 2050, EGCC could be 01/19. (Left and Right).
The next 'Geomagnetic Reversal', (like the Yellowstone 'Super-Volcano'), is way overdue.

When the runway at Farnborough was being re-surfaced, I realised it would change from '25' to '24' within 12 months, so I made some enquiries and found they calculate rates of change in 4 year 'epochs' rather than just as they show it on half mil charts, so it was actually due to change within a couple of months, thus we were able to paint the new surface with 06/24 rather than have to re-paint it within 12 months.