8 year old cocker regressing & messing at hight

Question
QUESTION: Our 8 year old cocker,who has been housebroken for years, is now regressing by messing at night. We take him outside 2 times in the evening, the last time right before bed. He goes into the bathroom and poops on the tile floor!

ANSWER: Any time a dog has a sudden behavioral change, it's time for a vet check up.

Also I'd like to know what you're feeding him and when.

---------- FOLLOW-UP ----------

QUESTION: Thank you for your answer. We have an appointment this week for shots and a check up. We feed him Nutro Senior. And he also gets 2 small Milkbone dog biscuits for 'dessert'. He is self feeding during the day and we pick up the bowl by PM. During the day he uses the doggie door to go out into the yard.

Answer
I'd stop the self feeding.  And Nutro is far from a premium dog food.
He doesn't need "senior" food and it's usually lower in protein which isn't good.

Please don't give him vacs before you get the bloodwork results from his checkup.  I'd take a stool sample with you and your vet should also do a urinalysis plus culture.