Hi,
Please could you take a look for me? I just made them up by myself.
The room has been being freezing since its air conditioning went out of order.
The room has been freezing since its air conditioning went out of order.
As he entered the classroom, the students had been being noisy for quite a while.
It's acceptable, but better is 'When he entered the classroom, the students had been noisy for quite a while'.
In February, I will have been being in the same position in this company since I started work there.
In February, I will have been in the same position in this company for a year.
To me, it doesn't make any difference to make these sentences by using prefect tense in stead of perfect progressive tense The difference is that non-progressive is better here and much less clumsy than progressive. My advice is not too worry too much about using perfect progressive, subject to what I said in my original post.
Best wishes, Clive