Sessions overlap question

Hello,

I’m new to forex and have been trading a demo account for a short time. From looking at the EUR/USD chart(I usually use 15 min) I’ve noticed that when the sessions overlap at 3 a.m. EST and againg at 8 a.m. EST there are usually big moves. The one at 3 a.m is usually around 20 pips and the one at 8 a.m. is around 40-75 pips.

Is this a recent thing, or are there large moves at these 2 times?

Thanks for any insight.