It is probably just to ensure that war, including prep takes 48 hours. Otherwise some squads would have about 20 wars a day !! The system already struggles to complete matchmaking in a reasonable time so they just need to slow things down.
Just my view but no other logical reason.
An ex-Amazon player, squeezing every last minute from the game..
Player name Dog. Biting rebs across the galaxy.
currently out of game