This one is not handmade - it looks like a proper highways sign - aluminium, reflective coat, etc. It really is an official advisory one-way. Like I say, I've never seen anything similar elsewhere.

Hi Gerd, Crossgreen drive is signposted as a recommended one-way (I can't remember the exact wording on the sign, but could look it it up if necessary; it's certainly something I've never seen elsewhere). I take that to mean that there's no legal order preventing other-way traffic, but that if everyone follows the advice, then traffic will flow more freely (the road isn't generally wide enough for two-way traffic).

Aerial photos can take a year or more to catch up on new developments.

Thanks - fixed in changeset/34722439.

Thanks - fix committed.

And a couple of missed speed limit fixes in south Livingston and Dumfriesshire.

It's not something I've ever done. It would look better done by you (to make clear it's not a hostile action!). If I were doing it, I'd start with the Wiki: osm.wiki/Change_rollback - is that any help?

I've noticed poor alignment of aerial photography in other places - most notably on steep slopes such as this zig-zag ascent west of Torridon: osm.org/#map=18/57.55422/-5.54483

Yes, my visits there (including a transit of the natural arch) corresponds much better with the OpenData outlines than with Bing aerial. I can probably dig out my track logs if you need to see them.

This outline appears very badly aligned, compared to OS OpenData and confirmed by my personal traces. Please can you revert this change? Thanks.

I was using StreetView on http://os.openstreetmap.org/sv/ - it seems not to have been updated since November.

I've changed the ref to A4017 as you suggest, and set old_ref to avoid any future confusion. (changeset/26762646)