I use ad substitute for a variety of purposes. More or less anything that isn't damage, guest price challenge, or a competitor pricematch. It's basically the miscellaneous/other option.
Example: Guest returns XBOX 360 copy of Disney Infinity they purchased on BF for $39.99, they wish to exchange it for the XBOX One version of the game. It won't allow an even exchange, but the two items are the same price, and were both on sale during BF.
I'd return the 360 copy to a giftcard, then mark down the XBOX One version to the return price and purchase it with the giftcard.
I'd use ad substitute for the markdown as it isn't a guest price challenge, the price that it typically rings up as is the correct price for most purposes, guest price challenge is only for items that ring up at the wrong price.
This way the pricechange doesn't show up on the price challenge log. (They're supposed to check for incorrect signage for any items that had a guest price chalenge occur on them each day to verify if the guest was correct and fix the issue if so.)
As for the grid, you should have access to myTime if you're actually a GSA. By "actually a GSA", I mean if your jobcode is GSA and you have supervisor #'s, as opposed to just getting scheduled GSA shifts without your jobcode being GSA.
