Thank you for the response, Daryl. The issue I run into when I follow your steps is that because I’ve set Notify Customer as ALAP, the task gets pushed back to the end of the project. Setting the lag up is fine – it spaces the tasks apart by 14 days. Because the Perform FAT has no predecessor, I can’t set a lag to that task.
I instead configured the Notify Customer as a predecessor to Perform FAT and set the lag on Notify Customer to -14 days. It kind of does what I want – the issue is that the Notify Customer task should technically be completed before the FAT is performed, though I can’t add in a lag if it does not have a predecessor. I’ve configured it as a milestone (zero duration) and as a Start-Finish relationship and it seems to be working.