I don't know if it helps at all, but I have seen immense frustration from many as to why their council is treated differently from neighbouring boroughs/councils.
I can't profess to have all the answers but I do know that such decisions are based on a wide range of criteria.
And one of the biggest changes of late in how the govt makes tiering decisions is by not only assessing individual councils/boroughs but also their neighbouring councils/boroughs.
My council was doing fairly "ok" when tier 4 was slapped on us weeks ago. But looking across all the councils surrounding us, it was so clear that the situation would deteriorate rapidly, sooner rather than later - which it sadly did.
I publish the cases data every day for every council in England on www.covidmessenger.com so I am close to the data and I can see trends emerging. And most of the time, its fairly clear why tiering decisions are taken.
If you want to check your council and your surrounding councils daily - quickly and easily, you are also welcome to on www.covidmessenger.com.
Given I run Covid Messenger, I have been at times forwarded non-public information on a trust basis and while I can't disclose the details of that, I would say that the scale of parameters being considered when tiering decisions are taken is vast - and hospital capacity and potential overflow from neighbouring hospitals are critical elements.
If you have low case rates locally but hospitals are filling up in neighbouring boroughs rapidly, then the area will usually be tiered up quickly to quell additional flow of local cases overhwelming hospital capacity. Simialrly, if your cases are rising but hospitals are miraculously coping and have spare capacity, that decision to tier up the area may be delayed. It's not a particularly transparent element, but the rate of fill up in neighbouring hospitals is quite critical as causes inevitable overflow that can overwhelm quickly.
It is so tremendously complex. And the media often try to distill it into a single angry soundbite which misrepresents the situation tremendously.