Hello!
Thanks for commenting 
Yes I checked the lightmap channels are on the correct co - ord , I also too had a moment a week ago where I thought I had accidently made the wrong face larger on the light map ! But I double checked it and it is the correct face.
Here’s the lightmap visualiser: lightmap density - i have some whack red results on the ivy and foliage at the moment, even though the foliage lightmaps do not overlap, this is another issue that this project is throwing up that I’ve not come across before, however the shadows that are causing the issue are being cast on the wall and floor pieces.
