I have researched alot about encopresis and i know for sure it aint that as when he is on school holidays over the summer he is fine goes to the toilet normal and had a normal poo he doesnt do this any other time other than at school and he know that he is dirty and when he done it. I have also been in the toilet with him when he goes and he has no pain or problems going, also asked him if he in pain and he says he isnt
You're treating this as a behavioral problem, but it sounds like the doctor was telling you it was encopresis. If so, please read up on encopresis. When he does poop, is it a normal, big, soft stool in a relatively large size, at least one a day? It just sounds like he is getting worse, and if the original diagnosis was of encopresis, he could still have it. It won't get better by itself. Over time, the large intestine can get so bloated that it can't return to its normal size, and the entire colon and large intestine can get full of hard, cementlike, impacted poop. The only thing that come through is a little bit of semi-liquidey poop around the edges. By then, the whole thing hurts so much that the child tries to avoid going to the bathroom at all.
It can take up to three months for a child to get over even the first stage of it and even longer for the colon to come back to normal. You have to continue to treat for it the whole time, not just give Modvicol for a while and then stop. The initial unclogging process can take several weeks (because of how much rock-hard stool has accumulated in the colon), which might mean two months or more of intensive laxative treatment and then follow-up with Metamucil in the diet. Some kids even need to have an endoscopy, in which a soft scope is inserted in through the rectum to break up the hard, impacted stool.
I would take him back to see the doctor with the suspicion that he never really got over the original problem. Please don't punish him for something that might be a physical condition and not a behavioral issue.