I did the GAP last year, from Pittsburgh to Cumberland - Cycleblaze journal
here.
The interactive map is usually the most up to date and they have a trail alerts section that is usually pretty current, too.
I found the interactive map kinda hard to use, though. The listings for lodging and food are not necessarily complete or up to date - better to look at Tripadvisor or Google for lodging/food planning. My choices for food and lodging in Confluence were very limited - no answer at several of the motels/inns shown on the loding list and many of the dining spots closed during the week when I went.
Covid has hit the small trail towns pretty hard, with many businesses closed or ending their seasons after Labor Day vs. staying open through leaf peepage season. West Newton, Connellsville and Meyersdale are pretty reliable still. - if you are planning food stops at the other small towns, check in advance.