He must have know about this post I made about him because last night he barked once, not very loud, and then stopped. No pee this morning when I came downstairs, so I think if he barks tonight I'll just ignore him. The only reason I didn't ignore him before was because sometimes he gets consistent and loud with his barks and I didn't want him waking my kids...Even though I didn't get up with him last night I'm still tired from the anticipation of his barking and the thought of getting up....

this might have just become a game or habit,if not a medical issue,

I have the same problem with my two. We take them out about 11:30 every night but it's rare that one of them doesn't want to go out between 2:00 and 3:00. They can go all day and not want to go out but it seems nighttime is another story.

Maybe another 'critter' is creeping around outside about that time and he senses it!

I know your feelings. My dog did the same thing...2:30 to 3 am for many mornings. I boarded him at the vets for 7 days while I wnt to visit my son. Since Petey is home he has been sleeping until I get up around 6:30 or 7 am.
Maybe the time away cured him I hope so.

I have a 4.5 yr old Lab -- last nite he ate an yarn ball about the size of a lemon. We took him to the all-night clinic and they induced vomiting. None of the wool came up. He has been lethargic most of the day but no wool in his poop. I spent the day trying to get him to have a "movement." So far, no results. I hope that the ball stays intac. Our regular vet says we should not worry unless he becomes he starts having diarrhea or starts acting funny. He is really clam which is unusual for him. He is about 4.5 yrs and has eaten several of my hair holders and they show up about 2-3 days. I have been trying to take him out every hour for about 30 min hoping that the this will help him get out of distress mode. Any ideas on how to make him poop w/o a scene? TY, eliza

get a doggie door!!!problem solved

Yup, sounds like he got into the habit of barking and then found out you would come and check on him. So, until you break that cycle, he has your attention.
Dogs are smart.

Definitely have him checked out for a bladder infection if his potty patterns suddenly change.
If that is ruled out, then you need to untrain his training you.
Kennel him at night. Also use the kennel for short periods during the day so he's ok with being in it.
If the kennel thing doesn't stop the behavior in a few days, try moving the kennel to the basement for the night. And invest in a pair of earplugs for a couple of nights. :) and stick to it. If you cave in, he will know that if he keeps barking you will come back.
If he neutered? If not, look into it. Then the gals in town won't be so interesting, and you may find that changes him back.

This is what we did with a frequent bladder caller.