you should report it, and LSAC will seriously investigate it.
they will likely not use that center or supervisor again, or lay out some serious consequences for the aforementioned. they might also try to look into which examinees it was and investigate their scores, which they should.
there is no evidence the person was using a backpack to help them, but a digital timer and scratch paper DEFINITELY gives a test taker a marked advantage. i wouldn't have said anything at the test center cause i wouldn't want to piss off the people who are timing and handling my exam, but i mean i didn't have a gallon sized bag and used two quart sized bags, and i called LSAC on the way and they said i could only bring in one bag, not two that were equal to or less than one gallon with regards to how much could fit in it (AND that the top had to be sealed!! my pencils didn't allow the quart sized bag to seal, but the proctor didn't care and i don't think it gave me an unfair advantage to have pencils lol)