The switch that happens isn't a conscious one (or no adults would need diapers!!!). It's a neurological one that goes from autonomic control (unconscious, like breathing, heart rate, etc.) to somatic (motor control, partly conscious).
It never FULLY switches over. Whenever you're scared, nervous, etc... people pee a lot more often (remember that for job interviews) even as adults. If an adult is REALLY scared, they'll still wet their pants. And the "I just sh*t myself" thing you hear from pilots, etc... isn't a joke. Well, it can be, but it happens.
Adrenaline YANKS control away from the conscious and into the unconscious. The longer you've been potty trained (like as an adult) the stronger the switch is. For kids, it can be really tenuous .
So if you're fighting at ALL, or they're upset at ALL... guess what? They have zero control.
You can spend the next 6mo-2years fighting (the more you fight the longer the process takes)... or you can take a few months off.
There's also a big difference between the KID being potty trained, and the parent being potty trained. If you're taking them to the bathroom every time they make that 'face', and every 30 minutes, and, and, and. and... the kid isn't potty trained. You are. I know a LOT of parents who say their child is (or was) potty trained at 1, 2, etc. SOME are. Most? Nope. Most of the time those "trained" kids are completely unable to recognize, retain, and release. It's the parents who are trained. Leave the kid with anyone else (or stop taking them every 15-30 minutes) and you have a soaking wet kid.
((Even babies 'hold it' for 15min-1 or 2 hours. The sphincter isn't just open all the time.))
Take a break. Let the adrenaline response wear off so the neurology actually has a chance to switch. Then when he's ready it will happen in a WEEK and not weeks and months. If it takes longer than a week, they're just not ready. Any by a week, that's 1-2 days of a lot of accidents. 1-2 days of a couple accidents. Then maybe 1 accident every few weeks (usually when....get this... they get really excited. The adrenaline.).
There is a HUGE difference in development in 6mo. Think newborn to 6mo. Think 6mo-1year.
Seriously. Drop this for now. Wait 6mo. Save EVERYONE the stress.
((Oh... and just as a heads up... it's common for poo training to not work for 6mo-1 year after pee training, and ditto for night training.))
Adrenaline