Apart from difficulties with what you mean by a real form of language, there is the problem that before we had real language (in fact for quite a while afterwards as well) we kept no formal records, so we have very little to go on. We can be thoroughly confident that by 15000 years BP there were many advanced  languages already well-established in general use.

However, we could make a (slightly rickety) case for the final emergence of human language coinciding fairly well with the emergence of Homo sapiens. Where would you put that? 50000 BP? 75000? 150000?

Suit yourself! How would you suggest we go about defending any one assertion against its rivals?

That depends on what you think of as 'Language'. If you're specifying a written language (or even a spoken one with grammar and syntax) then that would be somewhat later than sign-language and primal grunts. But signs and primal grunts can make up a 'language'. Man is a tribal, hunting animal and as such would need signs or grunts for 'over there', 'over here', you, me, us, them, food, enemy etc. Many animals communicate with each other and for that, they have a rudimentary 'language', even if we as humans wouldn't class it as one.