Changing dentist

I did this and have no regrets. Certainly no penalty.
I had to go on a waiting list and unfortunately had an emergency during that 6 months wait.
Definitely no regrets although my NHS dentist also does private work and has tempted me towards implants not on NHS.
I am very tempted.....

No! You don't belong to a dentist. Just cancel any appointments you have coming up.

I changed from private to private earlier this year, no penalties, my old dentist didn’t even know where I was going. I only moved as my existing dentist retired and parking at the location was impossible, I used to work nearby.