I’ve had this happen back when I was in research, only there was no visible change in the appearance of my boss, he would just flipflop back and forth between projects on a weekly basis. It didn’t help that he spent most of the time I worked for him in China instead of in his lab in the U.S. I hated that man so much.
My previous boss was the same way (hence why he’s a previous boss and not current…). He was most of the reason I liked working graveyard shifts there; I hardly saw him and the times I did were few and far between.
Didn’t stop him from calling me from his house from time to time to tell me how I was doing everything wrong, even though I was doing things the way he had told me to.