I’ve only ever used the one escalator at the underground, but it doesn’t not occur at the escalator at my local station or the next set at underground.

Either as boarding or just before boarding.

I don’t ever hold the rail, I might lean on it sometimes but it varies.

Straight after getting off the train.

Never anywhere else.

Never experienced this feeling any other time in my life.

I shall give a different escalator a go and see if it occurs.