Another day, another Banner saying ITVX is "fixed", and IT ISN'T as far as i can see :-(
whitesnake
This is a communication problem. Jack and I can only go on what is told to us. Here are the only three bits of information that we have to work with...

Is "Improved the support for downloading videos" the same as fixed? Your guess is as good as mine. And then on 2024-02-18 came this private message in reply to my asking for a status report.

This one clearly uses the word "fixed" and refers to the (future, at that time) release of 6.1.6.6. So, in the eyes and mind of Management, everything is fixed in 6.1.6.6 but Amazon and Netflix. But when the changelog for 6.1.6.6 comes out, only a limited number of streamers are mentioned in regard to DRM. WTF!

So we have a Hobson's choice. No matter what we put, the answer is wrong because we have no choice. Jack chose to use the second bit of information, and I agree with him totally. The third bit of information doesn't take away from what was written to us in the second bit.
Tell you what, for my own curiosity, list one or two episodes that you say aren't fixed. Take them from the basic subscription; I don't have ITVX Premium (or whatever it is called). Try to download the one or two episodes using 6.1.6.6, and attach the resulting full complete StreamFab.log to the message along with the list of the episodes.