7 month old cavalier humping

I have a 7 month old male Cavalier King Charles Spaniel. We adopted him from a shelter at 4 months old, and they neutered him. When we first brought him home (4 months old) he would try to hump is dog-brother, or us if we were sitting on the floor. We would firmly say “no” and redirect. It wasnt too often, and he quickly grew out of that phase with us. Yay.

Unfortunately there was a lot of humping in December. He would try to hump other small dogs, children, and our friends that owned dogs (assuming it was their scent). The human humping, especially children, I am not okay with. We spent a lot of our holidays watching him like a hawk making sure he wasn’t tying to hump anyone, which was a burden. We did had very similar socialization moments in November when he was 6 months old, and humping was not an issue with other small dogs or people then.

Again, he’s 7 months old and already neutered. I’m hoping this is just a phase and he’ll grow out of it? Is there anything else I can try doing to redirect this behavior?