Well it seems that it is pretty normal for the
to be able to hold it during the night.
During the night when we sleep (and when dogs sleep), our kidneys shut down and that is why we don't need to get up to go pee in the middle of our sleep, so we don't need to eliminate. So if a dog is sleeping for the whole 14 hours then it's okay, but if the dog doesn't sleep the whole 14 hours straight, then his kidneys are still working and trying to eliminate but there is no room for the urine to flow down the urinary tract, so some of it will stay inside and the rest will stay in the urethra and the bladder. It is when it is there for a long time that it can lead to infection because urine has impurities/toxins that the body is ridding itself of. You don't want that to remain in the organs so long.
This is what I thought too, as when we are younger we hold our bladders during the night, but now that I am older I do get up once during the night, but then again I do drink most of my liquid during the night too.
My Border Collie always held her bladder if we weren't home. We could go 12 hours easy to a wedding and reception, gone 12 hours and she would never mess in the house, but then too she didn't eat and probably didn't drink while we were gone. She would just sleep. Granted it didn't happen often, but I always remember my SIL having to hire a sitter for her Peke, or saying she had to get home quickly as Nikki was alone. As Nikki soiled whenever she had to go, no matter where she was.
Granted I have never left Luigi and Lia longer than 4 hours, and if I were gone longer than that I would be getting a sitter, cause BICHONS are just not dogs!
But I know they do eat, drink and pee regularly during their waking hours so I don't feel I have reason to worry too much. As the days get shorter and the nights longer, I’m sure our evening walks will decrease and all that evening peeing and marking will end and they will have to get back to peeing on last call, and usually our house does not get more than 7-8 hours sleep, as once someone is up and awake so is Lia, but Luigi, he is like Benji, a lazy teenager in the morning. Well ive thought about this alot and even asked my vets advice when Benji got neutered. B enji wees for england in the am but once 10pm comes around thats the end.
Did your vet give you any concrete advice or an answer? I think last call at 10 pm is ok, yes? Some of us like 8+ hours beauty sleep per night.