@JimM11 - Thank You for your help so far - sorry for the delay - I was trying to gather as much info as possible.
Firstly , in answer to some of the queries you have raised :
1) We are PC and Android users
2) We had 4 Deco X50 Units - and I even bought another one in frustration ! All Decos have remained switched off since 21 st Nov - the Channel Scanning was done afterwards - at least 24 hours later - I am not sure why these are still showing up on the Wifi Inspector . Also something called ' Willows Mesh' is also showing up and we stopped using this 2 months ago . I do not recognise any of the other SSIDs except ours which is EE-85M. We have no other Router or Mesh Device turned on currently or at the time of the scan .
3) My phone that I am using Netspot on ( Thank You for the recommendation ) is a Galaxy Note 10 plus and capable of handling Wifi 6.
4) Regarding Router Positioning - It cannot be positioned at Site X2 - there is no plug point there . Pre-Fibre , the Router used to be in the area of the Red Circle in the Hall underneath the stairs - we only got speeds of around 20-30 most of the time . We were told it was because of the stairs. OpenReach Engineer said we can't have it in the Hall as the wire length ( Red Arrowed Line ) would be too long and prone to disruption.
Fibre enters the property at the site of the double red arrow.
The Channel Scan Results at the different areas marked on the map are as follows :
This is at the area of the red circle in the hall ( most central point but underneath stairs - does have power supply ) and the PC Room marked X4 ( dining room on the map ) .
The above point was where the Deco X50 was positioned .
The Above Room X4 is in direct line of sight of the Router with no intervening walls or doors.
The next 2 channel scans are in the dining area and in the floor above the red circle in the hall .
The TV in this area struggles on Wifi .
On the 1st floor - just above the red point on the Ground Floor - I am struggling to get any more than - 70.
Netspot did the Wifi Heat Map of Ground Floor and First Floor :
On the Ground Floor , the Router is in the Study . The slight greenish tinge in the Kitchen/Family Area is from a disconncted but powered Mesh - Deco M5 which we were using for the last 6 years.
The slight greenish tinge in Bedroom 4 was a powered but disconnected Deco M5.
