Super, let me know if you have any questions.

One other thing which comes to mind if you’re going to be adding significant amounts of geometry (like this) is that you probably want to enable the OSMUK Cadastral Parcels overlay (in the Background Settings on the right) and ensure the aerial imagery is aligned to it before starting to add stuff, using the Imagery Offset settings further down that panel.

It looks like the alignment offset for Bing imagery here is 0,0, which is handy. But in other areas of the northwest it can be out by 1-2m. The offset of the aerial imagery changes every few years it’s updated, and it varies between different areas (even between neighbouring villages). The OSMUK Cadastral Parcels come from the Land Registry and are a source of ground truth for alignment (and also help with property boundaries where aerial imagery is unclear).

Hope that makes sense :)