Some articles about color changes:
https://hayfarmguy.com/can-turkeys-change-color/
https://www.gameandfishmag.com/editorial/how-to-read-a-turkeys-body-language/193075
That is something new to me to see. I know very little about turkeys, so I will tag @R2elk and @casportpony for more help. Have you also posted on the turkey forum? Here it is:
https://www.backyardchickens.com/forums/turkeys.20/