Loshon haRambam :


Tor is vary vague; Beis Yosef brings down several rishonim with the strongest opinion towards issur is, lechoira, Rashba, and after some shv"t Beis Yosef paskens that chemas akum is ok provided that (his words - cooked until) there are no drops of milk in it. In Sh"A, he further confirms the heiter - vaguely but firmly, unless local custom is strongly against it. Ramo confirms the heitar, adds a heitar to remove those potential drops of milk lekatchila and applies a matrix of local customs and how travellers should behave.

Notably, Beis Yosef quotes another rishon as quoting Yerushalmi saying just as it's prohibited to allow a prohibited item, it's also prohibited to prohibit an allowed item. And he concludes with an interesting loshon of "Kedai Hu Rambam Lismoch Olov". (same loshon is used, by a later source, regarding Bach and chodosh)

Some questions :
1. Is there an acharon and/or a rishon who unequivocally assers chemas akum ?
2. Why doesn't the author of psak regarding "chalav stam" use some of the halachic apparatus constructed by B"Y ?
Of course, all this is of purely educational value; consult your OPS rep for actual applications.

It wouldnt apply to chalav stam milk. Anyway, IIRC he does.