Dog keeping pooing surrounded by the house. ?

My 5yr old dog keeps pooping in the house at dark. He runs upstairs into one of the main bedrooms & has a dump right on the floor. I've also caught him in the exploit of lifting his leg on the duvet cover or side of bed! He's trained & has only started doing this recently ( almost 3 weeks). He's a healthy dog (but does have allergies) & is regularly wormed. I do have another dog (who's 12) & one cat. They adjectives get on well together. I can't figure out why he's doing this unless it's a dominant entry.

If I close all the bedroom doors, he will then poop on the hallway upstairs or sometimes bathroom whether the doors open a little bit. He does this every night minus fail when everyone is downstairs. But he will do it in front of people consequently leg it. He still asks to be let out so he can go to the toilet.

Anyone know why he's doing this? What could I try\do to make him stop this? Any tips would be response. Thank you
a good kick up the bottom will do the job (just kidding) has there be any change to the house hold is he getting enough attention or have you changed the time of his buffet times
my dog started doing this and i fed her later in the evening and in a minute don't have any problems
whether its just during the night, keep him leashed to you so he can't be in motion upstairs, crate him, or put a baby gate up so he can't go upstairs. Or only just go out with him at night so you know he's gone to the bathroom. whether he goes every night at a certain time, it wouldn't be that not easy just to remember to go outside beside him. good luck
Answers:    you need to watch him when he is out side . Dont just consent to him out , got out with him and make him stay out until he does his trade . and if he dont then you will know he needs to travel out several times maybe until he does . try feeding him earlier surrounded by the evening like 5 or so and if you free feed ( head off food all the time ) go to portion feeding resembling feeding in am and in pm
Is he neutered?
If not - that is your first step.

I crate my dog at hours of darkness so I don't have to wake up to "presents".

He sleeps better in his crate, and so do we!
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