They said they are using Accelerator 3.0.

I just went and looked and noticed something. My software says "Accelerator 3 - Level 2". I remember they came out with a watered down Accelerator "Accelerator lite" ??? Could it be that is Accelerator 3 - Level 1 ??? And that has now been made available without special permissions? I don't know.
But surely that is still dealer restricted? How are they using it without a dealer account?

[edit] Just to be clear, I'm not salty at dng78hd. At most I'm salty at URC because they make dealers jump thru all these f^n hoops and force us to spend money - and then give the same crap away to any & everyone.
My suspicion is the original poster is posing as a dealer to URC and has dealer access. Looking at the list of equipment, they probably ordered (at dealer cost) enough stuff to get approved for TC. The rest of the requirements... who knows.

[edit again] But then if they have dealer access, why would they be learning things from YouTube videos, when they have all the dealer training material on the dealer site. I have no idea what's going on.

Perhaps the previous owners dealer gave them a login that was passed to the OP when they bought the house.

But that would mean the customer could login to the dealer's website and order equipment on that dealers dime. That would have to be a serious dumb a$$ to give away their company's login info. I wouldn't give my own family members login to a personal site, let alone a business account that could lead to me getting screwed up in a major way.

I only have a couple of TC systems out there and they are basic. Never used their amps. I hate hearing you had so much trouble with the systems, but I'm glad I never ran into any of that :)
CCP remotes have always been solid, taking care to avoid the trouble ones every now & then. And those usually can take care of most customer's needs.

[edit] I looked at the OP profile, wondering if we scared them off unintentionally. They apparently are from England. So maybe they have a whole different set of rules for this kind of thing and having access to the software. I know Europe and the EU in particular have strict rules sometimes about companies locking customers out of product they paid for.

He said he bought his house that came with the system. Perhaps there is a cracked version? Perhaps the previous owners dealer gave them a login that was passed to the OP when they bought the house. Who knows. URC has always been shady and I cut ties not because I had enough, it because they cut my dealership off after my numbers dropped which only happened cause I had so many issues with both hardware and software bugs, that I couldn't keep pumping their crap into clients houses. As a one man show, 95% of my issues were from URC and I couldn't keep up with the trouble calls. Failed amps, processors, remotes failing, they just kept adding up. Final straw to stop selling until they ironed stuff out was a job where all video control just shit the bed. 14 tvs, on a Friday, huge party that client hosts for the town the following day, in which they display content to the tvs via JAP. Multiple calls to TS with no resolution. I was there all day, 10 hours. Finally called one last time, which was my 4th call if I remember correctly and the tech immediately knew the issue, was a bug in the firmware, and sent a beta copy of accelerator that immediately fixed the issue. So after all the hardware failures and everything, this was the straw that broke the camels back. The fact every TS agent wasn't made aware of this, incredible. I made the decision to stop adding urc in new systems until they fixed these issues, and then during the pandemic, they decided to cut me off due to this, so F em.

you can have multiple logins tied to your dealer account and give them permission for certain things only

Really!? I did not know that.
I'm a one man shop so never had the need to do that.

[edit] I just went and looked. I can't find anywhere on the website to do that. I'm guessing you have to call in and have your account rep do it.

So.... you are not a dealer???
How the hell are you able to use the software then?

They said they are using Accelerator 3.0.

My suspicion is the original poster is posing as a dealer to URC and has dealer access. Looking at the list of equipment, they probably ordered (at dealer cost) enough stuff to get approved for TC. The rest of the requirements... who knows.

Think the thread has gone way off topic here lol so let me ask another question. 5 zones, 3 with TVs, Apple TV, Fire TV and Sonos, all prewired to one spot, Rako lighting, how would you go about replacing the same functionality I currently have with a TRC-1080 remote?

I would say that the old URC home theater receiver should be replaced. It wasn't that great of a unit when it was new. It doesn't do anything special for you over a good brand name receiver. And it doesn't support any of the modern 4K video formats (and audio decoding).