I've undone the deletions and made what I hope are all the needed updates and corrections. I made the entrance way from the south a service road (as there are other properties as well as the farm), the tracks that don't carry public footpaths access=private with gates where I can see them (eg to N ), and all the public footpaths are set as foot=designated, designation=public_footpath on footways and same with vehicle=private where the public footpath is carried by a track. I put the path behind the first hedge at the immediate east of the farmyard. Also had a go at updating the new housing 'Paddock Green' as far as known. Have a good look at see if anything needs further adjustment, and you can retry changing and/or comment here.

wrong, reset main line of A6 to trunk

I could say the same about every church and street - all St + name, not as you changed 100+ to Saint

This substation is in a private housing area, gated, private access. Unless you copied the name from a database?

Certainly: read osm.wiki/Relations_are_not_categories
Also read the discussion with you from 2 months ago at changeset/171884705
This relation, as created by you (and the next 60 versions modified by you) is about 0% complete of the coverage of the UK its name proposes. How many more versions are required to complete it and maintain it? Noone else is going to waste their time helping with this.
You can get all the substations in any required geographical area with an Overpass Turbo query, filter at will on voltage, operator etc according to the tags available, and it is automatically completely up to date with everyone in the OSM community helping.

This changeset changed the access for motor vehicles on way
way/461119575
as if the restriction sign (bus + taxi, bicycle and motorbike only 7am to 7pm) had been removed, but leaving the conditional restriction tags in place. Which is it? sign still there (tagging was correct as it was) or sign removed (conditional restriction needs deleting) ?
Please respond to changeset comments

Fully reverted.

@World_Winner next time tell your customer that their request is completely unacceptable. However you are responsible for your edits and will be reported for vandalism if necessary

2 unintended node drags reverted in changeset/175060890. (Intended cycle-related changes are retained). Node drags can happen on moving the map during editing in iD, if the cursor is on a map point at the start of the drag/move action.

Unintended dragged node repaired. This can happen when trying to move the map in iD while editting, if the cursor was on a map point. No harm done.

Unintended dragged node repaired. This can happen when trying to move the map in iD while editting, if the cursor was on a map point. No harm done.

At least the ones that match are candidates for clearing the name without loss of information.
But there are errors too, I had noted w.1425467008 (and 3 adjacent) where one field has BN1 2xx and the other BN2 1xx.
And setting your query to "!=" I see w.1432593337 with a random typo/mismatch.
But there are also shape errors, I noted one of the final ones (added *after* your discussion had concluded!) at the N of Peacehaven,
w. 1436971553 managed to get both 10 Telscombe Road and 10 Greenacre - but at least this sort of error suggests they might be deriving the areas themselves not copying directly from a copyright source.
I can see where one could get the areas where a small road has 1 postcode, or 2 for odds vs evens, but not sure how they got (or how we can verify) where a longer road has a change midway eg w. 1416829146 BN2 4TE starts from no.96, and 4TF up to no.94.
But there is probably no big hurry, if we're happy to change these tags by very careful overpass+josm edits rather than reverting.
A bunch of unwanted St->Saint edits are getting gradually edited back.
There's some bad 3D work but the worst can get fixed up. Some arbitrary/random? colour, height values though, and a general lack of care.
And there are also some type=site relations by the user which are just grouping stuff in categories and can go at some point.
Cebderby (Clive)

Good. There are around 1300 landuse=residential + name from this user along the coast from Ferring to Friston when one might expect maybe below 100 named areas in an region this size. On overpass I found 958 with name="BN"... The user did add a few more in 2 changesets dated after this discussion, but seems to have stopped now.
There are also a load with the town/area as name, which is slightly less wrong, but still wrong. eg for "Peacehaven" you would expect either 0 or 1 residential area named this, but there are 173; 59 as Woodingdean; 51 Newhaven; 31 Saltdean etc.

Excellent work. The only alt_name I would consider is the version without the apostrophe eg St George's Road (way/26726656) had alt_name=St Georges Road at v#14 before it got wrongly expanded at v#15. That form seems increasingly frequent on road signs, so maybe worth recording if you see any addresses using it, otherwise just stick with the basic correct form I think.

I am entirely familiar with it. I suggest you read the page you link to, including the parts you don't agree with. eg paragraph 2 not just paragraph 1.

For info, there are entrances at both ends, both more or less equal status and mapped in some detail. At both ends, the entrances share parts of the buildings with offices etc above, the station being underground. At the north end, even the ticket hall is underground, under the Conductor pub. At the south end, a central part of the ground floor of that building is dedicated to the station.
The station node used to be at the south end of Fleet Place which was definitely confusing, but the current mid-platform location is probably the best we can do.

Where the sidewalk is continuously adjacent to the carriageway (no big grass areas etc just an immediate kerb), and has no special access (eg shared cycleway), then the extra footway is a duplicate way. The public highway is mapped and carries the foot traffic. We don't add a second footway beside a farm track if it has a public footpath, we add foot= and designation= to the way. This is just the same; a duplicate way offering no choice of route but adding massively to the complexity of the foot routing calculations and the maintenance of the map. The path here is a massive GPS routing trap, which says that if you route to or from anywhere in the block around Walmer Gardens (gardens) then you MUST go via the E connection of Walmer Gardens (road) and Erlesmere Gardens (road). This is fiction, bad mapping, bad routing.

It's a marginal case. Compared to how it was, it was made dual and feels like it. The river bridge has old and new halves with a physical division, and the W arm of the T junction has a more-than-minimal island and about a 13m spacing between E and W bound. So this section is divided. Beyond that, it's a question of where these 2 ways meet - functionally it's good as it is and OS OpenMap Local agrees. For OSM, the join points back to a single way could be shorter if people want.

Good spot, thanks. Tidied up in ch. 165894556

The addition (not mentioned in your changeset comment) of an airfield, 3 runways and a perimeter track - all marked as if active - is reverted. The remnants of the perimeter way were already accurately mapped, the rest is historic/gone and correctly mapped as farmland etc.

Not sure about that:
https://archaeology.co.uk/articles/news/the-rose-rises-again.htm

Thanks for the clarification. Unfortunately - as my comments and changes showed - I don't take this interpretation; seems we'll likely not agree between us and this will probably need others to comment here or somewhere like talk.gb to get a consensus.