You're right of course, but this sort of thing happens whenever there is a poor signal-to-noise ratio. Like any Broadcast service, VLF timekeeping relies on a

You're right of course, but this sort of thing happens whenever there is a poor signal-to-noise ratio. Like any Broadcast service, VLF timekeeping relies on a saturation signal so it can override domestic electrical noise. The level of Electrical Interference is steadily increasing world wide. Already services such as AM Broadcast Radio are unusable for many people. The problem is caused by (1) the laws of physics, and (2) by our compromised EMC regulations. At least your European EMC laws are much improved over the watered-down American ones. Bottom line: The issue is much bigger than just VLF Time keeping.