Later I saw that the maximum power output was 2458 Watt.
Well, I definitely can't make these power numbers.
The battery in the P2M is good (according to my Garmin readout).
Just a hick-up of the power meter and nothing to worry about?
Sometimes it helps if you send in the power file simply so we can have a better idea of what's going on. Occasionally there's outside interference that causes the drop or the spike since ANT+ shares the same frequency as a number of other devices. Without seeing any of the raw data, that's what I would guess happened on your ride. Is it happening consistently or just ocassionally?
Thank you for the answer.
So far, it happened only once.
I was riding alone, no other Ant+ devices in the neighbourhood.
I have removed the wrong data points in Golden Cheetah.