Info button on a ticket order

I'm sure we're in a similar situation as other orgs where we have a lot of staff that have been on furlough for a year or two returning to work. Today, I was asked a question that I cannot answer.

We are on Tessitura version 15.1 21. In a previous version, when you added a line item to an order that had a Sales Note that was set to not required, the INFO button would show up as Yellow. When the Sales Note was set to Required on the performance, the INFO button would be red. 

In our current version, the INFO button only shows up when there is a non-required note on the performance and when the sales note is required, a warning triangle shows up beside the INFO button. Can anyone tell me when this change was made? I've searched through all of the Whats New in Version 15 documentation and cannot find this information.