Good morning Weaver, thanks for your helpful response.
Your post is incredibly interesting to me as a potential Andrews and Arnold customer as not only is your reply informative and well written, it also re-enforces what I suspected to be true, that A&A is an excellent company, the kind I like to do business with.
I'll have to see what the release terms are in my current contract with Zen, but based on what yourself and others have told me, now may be a good time to make the move to a company that I think may represent me better as a customer.
I've not had a bad experience with Zen per se and I've been a customer for a fair few years now, but in my opinion you are correct in your observations that they might not be the company they used to be. To be fair to Zen, I AM quite a demanding customer and doubt I am a typical Zen user.
For me at least, it appears that as Zen have increased in size and popularity they have (perhaps out of necessity) adopted the default setting of assuming a very low level of technical knowledge in their customer base and thus begun to use an increasing number of scripts to assist with calls, rather than try to ascertain the level of technical knowledge of the caller and tailor their approach accordingly.
This is fine for someone that simply wants a working internet connection and phone line at the most basic level (most likely 99% of Zen's customer base), However, because I have a (marginally) higher level of technical knowledge and understand roughly the speeds I should / shouldn't be achieving based on similar lines and conditions locally, I prefer to try to maximise the potential of the line.
This is the reason I feel I'll most likely be better represented by a more specialised company, such as A&A in the future.
For me, the move to mass market penetration has had the effect of Zen becoming less like the Zen of old and more like any other mass market Openreach based provider already available and the adopting of generic scripts to triage customer service issues has defeated the purpose of why I originally chose Zen as my ISP.
Changing the subject slightly, I'm incredibly excited to hear of your experience with the Firebrick, I currently use a Firewalla Gold for routing purposes (which I've found to be far more solid than the typical "high end" router offerings from Asus / Netgear etc) and I pair this with a WiFi 6 access point for what I consider to be a pretty robost and reliable solution overall - but I'm always on the lookout for new equipment that improves either security / performance / stabilty or all three within my home network.
I've had a look at the Firebrick (they're available on Amazon and also through A&A themselves), I've also played around with the online demo on the Firebrick website in the past and was a big fan of the software experience and features available, but I'd be extremely interested to hear your thoughts as a day to day user of the Firebrick hardware?