Fair enough, there was not enough evidence in the discussion raised. If more comes I'll bring it up in this edit again.,

875878531 - hatched markings act as an island here
208137299 - same as above
208286770 - trunk_link should be used for ramps onto dual carriageways, this is the case here
875878536 - again, the hatchings are here separating the road and slip road, and the incorrect road types were used, so if that was you please do not use tertiary_link for anything but tertiary roads.

See here for details https://www.sabre-roads.org.uk/forum/viewtopic.php?f=1&t=42039. Consensus thus far is non trunk, I suggest waiting a few days if more information comes through then appropriate action will be taken

This is trunk for many reasons, most notably the signs are green along the length and the national mapping agency for GB marks it as trunk also.
Do you have evidence to say it should be primary?

Whilst it may be contrary to OSM guidelines, in the UK roundabouts have no assigned status. On map-directional signs roads come in 3 widths depending on what status the road is. Roundabouts have a special fourth width meaning they are a class of their own.

The road numbered sections are correct. You sometimes have to ignore signage as they are signed with convenient numbers rather than the real ones. The section of road from M6(E) to M42(N) is the M6 Toll, albeit without any toll being paid. This sign mentions both M6 Toll and M42, neither are in brackets https://www.google.co.uk/maps/@52.4774418,-1.6850751,3a,26.2y,281.9h,96.64t/data=!3m6!1e1!3m4!1s1Zac0x6vWDG8P7KLdI2Gtg!2e0!7i16384!8i8192?hl=en-GB
From the other side the road is signed as the M6
https://www.google.co.uk/maps/@52.5000562,-1.7193536,3a,49.3y,160.03h,98.83t/data=!3m6!1e1!3m4!1skDfrw0tdfFNQMiNFpP3jjw!2e0!7i13312!8i6656?hl=en-GB
Here we see a sign for the M6 Toll before the M42 merges in https://www.google.co.uk/maps/@52.4835727,-1.7098868,3a,24.8y,293.71h,90.97t/data=!3m6!1e1!3m4!1skSMeUxLZcNRFXgifNL8DnQ!2e0!7i16384!8i8192?hl=en-GB
This means that the M6 Toll starts on the M6, multiplexes with the M42 and then branches off to join the M6 again further north.

First; a common turning movement does not mean the move is allowed or safe. This sounds like a selfish manoeuvre. About the trunk link segments; ramps or ramp like roads joining a dual carriageway or similar should be mapped as the higher class of road; in this case the trunk road.

The banned turn is implied; a u-turn at these locations would be dangerous and should not be recommended at all when using directions. If you think otherwise, correct these turns - do not revert the entire changelog

Trains run between Shepherdwell and Eythorne. Special trains run along the track to Wigmore Lane at times but there is no platform or station there

My mistake, I joined the segments to create a perfect circle. I shall fix the route relations

The roundabout numbering is something applied from the road signs of the UK. The roundabout has a special status of its own and is technically not a part of any through route using it. The change of the tertiary road is for the reasons that the road is a dead end, only construction traffic seemingly would use it to that end and it makes the map look more appealing.

The term trunk road has not been used to describe roads in the UK in the past couple decades. The status' are: Motorway, Primary, Non-Primary & B-road (corresponding Motorway, Trunk, Primary & Secondary in OSM)

Disagree about status; road is marked as primary on many paper maps and signs, incorrect signs in Newbury. If I deleted some roundabout junction tags that was a mistake. The dual carriageway sections I modified were incorrect and were 2 lanes separated by hatched road markings.

Not used in any way apart from councils tagging roads in their database

Because it is the terminal end of the A9000

The "Beesworth" name plate on the signs is a fictional place https://www.roads.org.uk/blog/theres-no-such-thing-beesworth

It's been removed from most maps, though now I'm unsure. Knowing KCC, they've either forgotten to remove it from this list or not told anyone it's still there.

There's lots of different names for junctions/interchanges/ramps etc so the name alone suits this.

Hi. About the cycleway, you're right. I forgot to add these dismount tags back when removing the crossing line before. I'll add those back. As for the roundabout, they don't really carry road numbers as all roads from it have equal priority, and no road number is on top. The Glanty is different however, as it's not a roundabout anymore, so it carries the A30 number.

As there is no path line segments, the path is considered to be a part of the road segments, hence in these locations I believe the crossings were unnecessary. Do feel free to add them back if you thought I acted rashly.