At the top of the screen:
"A special 24-hour VXP "weekend" is happening now! Unidentified Raiders 50 and 100 will spawn around Nav Relays, through Sunday, 9/30 at 9pm PDT. "
Through Sunday at 9 pm is much different than 24 hours from the start, which would be 9 am PDT on Saturday.
Sooooooooooooo how long will it really last?