@dredmorbius I believe I have collected all of your links here, for later perusal (along with redacted copies of all documents thus far exchanged): https://htyp.org/Frontier_Communications/2019-03-25_Woozle_dispute
I have started a project on my billing app for this. Every time I find myself worrying about money*, I will do a bit more work on this, and I will track the time spent.
Thank you all for your supportive comments, and Morbius especially for his research.
* aka every day