[rick.oliver]

I don't recall seeing an announcement concerning the number of teams which will be invited to attend the Championship events in 2017.

What is the source of the 400 teams per event?

The May 5, 2015 announcement states, "The details for Waitlist slots, along with the number of earned slots assigned to each FRC District, each FTC Super Regional event and countries outside the U.S., and each FLL and FLLJr. region and Partner are still being worked out."