Within the United Kingdom (or perhaps just England and maybe Wales?), academic pay scales are divided over different pay grades. Annual salaries outside London range from £16,131 in the bottom of grade 1 to £65,454 at the top of grade 10. For example, see Oxford Iniversity, University College London, University of Reading, University of Leicester, etc.
It appears the pay scales are uniform (albeit with a London bonus), but is there any uniformity of the definition of the roles corresponding to each grade? In one example I am familiar with, grades 6 and 7 are effectively postdocs (where grade 7 can be PI but grade 6 cannot), but this is one example for one role at one university. It does appear grades 6 and above are usually/always considered different from grades 5 and below, perhaps due to requiring a PhD. I wonder if any rules apply nationally.
How are the roles corresponding to academic grades defined within the United Kingdom? In case there are differences between constituent countries, I welcome answers for all countries.
This similar question and its answers make no mention of academic grades, and therefore this does not answer my question.