> Does this mean grid-synced clocks in the south-east part are now permanently ahead of the atomic reference, or are they planning a mitigation (which I assume would have to mean disconnecting again and running the SE part slower for a bit)?
That's the standard procedure. Maintaining an exact frequency can be hard, but counting cycles is easy. So the frequency will slew to slowly compensate back.
That's the standard procedure. Maintaining an exact frequency can be hard, but counting cycles is easy. So the frequency will slew to slowly compensate back.
Edit: Here's a Tom Scott video on a UK–Continental divergence that happened a while back: https://www.youtube.com/watch?v=bij-JjzCa7o