Do they know the have BPD?

Dated somebody with (what I believe is) BPD. Didn't even make it to the end of the honey moon phase, cause something else came up and splitting came after 4-5 weeks approx.

They are in therapy since on an off 3 years. But I wonder if they have been told the diagnosis of BPD or not. It seems rather not. What is your experience? Does their therapist tell them straight forward or do they speak general stuff about "having a tendency in certain situations" and so on?

Could there be a difference how therapists handle this in US and in Europe? Or can it even differ from therapist to therapist?

TIA