He's 4 months old now. I was told by the breed the hair will come at around 4 months unless i misunderstood. So....when will he'll start shediing?

Well, since all my dogs are rescues who are well into their adult coat, I had to go looking.

It seems to range between 4 months (or so of course) on up to around a year - apparently depending on the dog.  What you'll see first is the presence of longer hair - his guard hair - coming in over his juvenile hair, then he'll gradually lose that juvenile hair -or- he may just blow the juvenile coat as his adult undercoat comes in.

I'm not a lot of help since, as I said my dogs were all adults when I got them and looking on the web doesn't seem to give anything resembling a definitive answer.

Spider started losing her puppy coat at about 6 months old. Came out as her first real winter coat came in. Might be slightly inaccurate based on spider being a mix. But it is my understanding that as far as coats go, a sibe/wolf and a pure sibe would be on similar timelines with coats. It is also my understanding that where you actually live will effect when they blow their coat.