I didn't experience anything like that.
I always found tons of event RB lying around most of the time.
Except during evening time, event RB do decrease.

Also, this event not allow player to summon broken boss in 1st part.
So many player like me prefer to keep summon item to use in 2nd part.

More important, we have new Aqua-shadow mission.
Many player, of course like me prefer to spamming Aqua-shadow mission more than play event.
All the stone, medal in Aqua-shadow map are important thing in long run.