I spoke too soon.  Here's what FIRST has said:

SPIKE Prime will be approved for use in FIRST® LEGO® League starting in August 2019, and will participate alongside Mindstorms EV3, NXT, and RCX.  

Steve Scherr
Virginia-DC FLL Referee Advisor

On Thu, Apr 4, 2019 at 1:13 PM VA-DC FLL Referee Advisor <[log in to unmask]> wrote:
Because shipping is not until August, my guess is that the Spike Hub won’t be permitted as a controller. Probably everything else, though. 

We may hear something more at World Festival in a few weeks. 

Steve Scherr
Virginia-DC FLL Referee Advisor

---- On Thu, 04 Apr 2019 11:46:41 -0400 Skip Morrow<[log in to unmask]> wrote ----

Lego announced the Spike Prime a few days ago, and I am seeing rumors that it may be acceptable for FLL:

Will Spike Prime be permitted for VA-DC?

Skip Morrow

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