Is this better or worse?

My partner has been working through his PA for the past few months now and it’s been good. He’s adamantly against it morally and is taking all the necessary steps to get better. However, now when he has the urges, he m*sturbates to photos of me. This was fine until it became excessive. Sometimes he’s doing it multiple nights in a row and says he isn’t even horny. I feel like he’s just replaced the catalyst. It’s like if he quit smoking cigarettes and went to a vape. I’m not MAD because it’s not like he’s lying and going behind my back to look at other people. I’m just scared that this is just another form of PA and how it might affect our relationship. And yes, he’s already aware that this habit (frequent m*sturbating no matter the content he’s viewing) he’s picked up is bad and he needs to stop it.