No, I wasn't confusing those. Let me put this way. Unless what I'm reading is blatantly wrong, the claims of rabbis about what is "biblically" prohibited have been under dispute and changed over the centuries. So it may not be a "rabbinical" rule but it came from rabbis and didn't directly follow from the bible and the rules for interpreting the words of the bible. (Unless a huge series of rabbis were just flat-out wrong.)
There are indeed things that are disputed if they are biblically prohibited or rabbinically. Usually it's not the nature of the item that is disputed but the degree.
But not meat and milk. That has not changed. So if what you are reading is saying that, then yes, it's blatantly wrong.
For example the time delay in between eating meat and milk: That's in dispute. It's a multi level dispute, of: what delay is biblically required (if any), and what how much of a delay is rabbinically required (the two numbers are not the same), and how large a delay is required depending on which food was eaten first, and the type of food (aged cheese, young cheese, or milk).
But eating them together? Absolutely no dispute.
Just as a side note, there is a tendency to say "Rabbinically required, oh that's not as important." But the requirement to obey rabbinical prohibitions is itself biblical. So once a rabbinical edict is accepted it has total and complete force of law with virtually no distinctions between it and biblical edicts.
