Quickly picking up two Boxes that both contain champions gives nothing in the second Box

Description / Steps to reproduce: Have plenty of bench space. Get two PvE Box drops that both contain champions. Touch box 1 and it starts flying toward the first spot on the bench. Touch box 2 and it starts flying toward the SAME first spot on the bench. Then Box 1 opens and gives you champions. Box 2 hits the first bench slot ( which is now occupied by a champion from Box 1), and Box 2 gives you nothing.

Expected result: Both boxes should give you champions. Box 1 should reserve x spots on your bench immediately upon touch so that Box 2 can't target a bench spot that will be occupied in the near future. The player should be locked out of moving existing units to those reserved slots too.

Observed result: Box 2 gives no champions and no gold.

How to circumvent the bug currently: Pick up box 1, wait for it to fully open, then pick up box 2.