I’ve found anytime before two. There’s a bit of research around this, also, since they reach a new level of independence and autonomy that makes pretty training incredibly difficult.
I’m going through the same thing. My baby is also taking off her diapers. I tried last week potty training, but she’s not ready to sit on it yet. I even took her to the bathroom, sat down myself, and encouraged her to sit, but she still refuses.
We bought the course from big little feelings on instagram. Best thing. She was potty trained in 3 days only one accident. She started going right away. But she can also communicate (2 and a half) and she can tell me when she has to go and she does it all by herself. There are some things you have see to check if he is ready. Seems a bit early at 14 months.