Yeah …… you haven't a hope in hell of getting that exhaustive list fulfilled.
Don't worry, I do understand the frustration involved in trying to get a fault resolved, especially a tiny one like yours. But, I'm only here to give you the benefit of my experience.
You need to first choose which path you are going to take, to report your fault ? Network, or Broadband ?
If it's Network, then (as with all reports), they will run a line test that I'm guessing will pass with flying colours, going off the symptoms of your fault. They will then read the script about potential charges. You accept, and they proceed to build a CDTA (Concsious Decision To Appoint) task.
The criteria laid out for this type of task is …... we perform a PQT, we perform an Eclipse/Fast Test, if these both pass and no audible noise is heard on the line, then it's goodbye and you get the bill. No amount of protestation about SNRm fluctuations will cut the mustard. If it is a CDTA task, that's all we are empowered to do.
If you go down the broadband path, you really are in the lap of the gods as to what engineer you get and what they are prepared to accept as an 'issue' with your circuit. They will have to run the mandatory PQT and Eclipse/Fast Test, but can also run a 'DSL Close-out test' ) for 5 or 15 mins), that pings data about for the allotted time looking for errors. If all 3 tests pass, then again I would guess your ISP will throw the bill for work done, your way ??
This may sound harsh, but it's not meant in that manner. All patches have a couple of, how shall I say it …. Konrado's. Chasing down ridiculous fluctuations that are basically part of the systems management tool. I'm not saying this is you, Chrysalis, but there HAS to be a cut-off point where we say the line is performing within expectations. This is a generalisation, and you may well have a decent HR-type fault brewing, I'm just putting over our remit, as agreed with all the ISP's and Ofcom, as you asked for views before you go ahead and report.
By way of a PS ……… if you do go ahead, I think you'd get more bang for your buck if you go down the broadband path. If you do, request that the engineer use 'Quiet Line Test' and also ring your landline whilst the circuit is undergoing the DSL Close-out test. If there is a HR, then chances are the errors will increment under this particular 'loading' test ??