potty training regression in 6 month old

Question
Hi there, I have a 6 month old english bulldog that has been doing great with her
Potty training for the last 3 months, but now for the last week and a half she has been
Having accidents at night time almost every night. I have just changed her feeding
Times from three times a day to twice a day at 8 in the morning and 3 in the afternoon.
The rest of her routine haven't changed at all. We are at the vet a lot for vaccinations,
deworming and check-ups so I don't think its anything medical. Also the weather changed
to winter could it be the cold weather?  Please need some advise
Thanks for your time!

Answer
It's winter in the UK????  or has this been going on since winter????

Any lapse in training is always the fault of the training.  Go back to square one: go OUT with the dog every three hours, reward (with tiny tidbit) and praise every urination; indoors, keep an eye on the dog so as to avert accidents.  Interrupt by clap of hands and happily take dog out, don't get angry, yell "no", etc.  Repeatedly TAKE dog out over the course of two weeks, then increase time to four hours; give puppy ample and fair opportunity both in time you are out there and outings during the day, at least five for a young dog that's having problems.  Is this puppy spayed? If not, this may be hormonal: ask the vet.  If the puppy dislikes cold weather (as many short coated dogs do!), buy her a coat or sweater but persist in your training.  Encourage her on your outings by saying "go pee", staying in or near the same area (where her scent will be in the ground); within a short time, she will know what "go pee" means and she will also understand that urinating outdoors is rewarding.  If she still persists in urinating overnight, it may be physical (if she's been spayed recently, there may have been a bladder injury), she may be totally unaware that she's urinating (in her sleep), I'd get a second veterinary opinion if this is the case as the original veterinarian is not likely to admit to such a surgical injury.  If you are waiting too long between evening/night time outings and morning outings, this could also explain it.  Just re-train her as suggested and wait to see if this condition continues even when it's clear the dog understands she is supposed to urinate outdoors.