It makes the same amount of sense to prevent players from attacking in the last seconds of war as it would to allow a player to continue attacking after the 24 hours ended. If you really want the war day to be a hard 24 hours, then barely 15 seconds into your attack, the war should end, you lose all your troops, and you still lose. Rather than allow players to attack late and force a new mechanic that would end an attack prematurely, they chose to prevent players from attacking in the last seconds of battle day. It’s unfortunate that you got caught by this, but it’s nothing new. Wars have been this way all along. There are many, many threads about it going back to the beginning.
https://forum.supercell.com/showthre...s-about-to-end