What kind of monster plots a time series vertically?

The news reports I’ve read suggest that it started at 6:33 am, hours before the actual outage.

Edit: I must be remembering this wrong, I can only find references to 9:30 am, not 6:33.

See: https://www.france24.com/en/europe/20250430-what-we-know-so-far-about-the-massive-blackout-that-hit-spain-and-portugal