There's a very high probability that the man who made the 999 call at 23.18pm and who called to have just driven past the flats, was driving west to east along Forest road with the flats on his right.
He then drives past only 1 of 2 signs for the building that reads "St David's Court." (one on Forest road, the other at the back in Parkstone Road that isn't visible from the main road.)
As he approaches the building he sees the flames and reads the sign on the frontage of the building that reads "St David's Court."
He then gets to the traffic lights and almost certainly turns LEFT into Fulbourne Road which leads northward to Chingford; a location that the caller mentions specifically in the full 999 call.
The reason IMO why he doesn't continue east along Fulbourne Road, park up and then walk 4 minutes up Fulbourne Road to the public phone box, is because there was ANOTHER public phone box less than half the distance from the Fulbourne Road phone box, that was directly next to the first layby on the left after you pass the traffic lights (just before the Bus Stop that heads eastbound.)
So if the 999 caller had driven past, seen the fire, driven straight across the lights and parked up on his left (facing east) then he would have used the phone box next to him; which has a perfect line of sight to the flats.
If he did continue along Forest Road, and chose not use the phone box next to him, he would have instead needed to have walked back towards the traffic lights, turned right and then up Fulbourne Road to the phone box in which the 999 call was made.
The idea of the man continuing east along Forest Road therefore makes no logical sense.
That IMO proves that he turned LEFT at the lights, and then as he drove north up Fulbourne Road, he notices the phone box on the other side of the road, so he parks up on his left and then crosses the road and goes in to use the phone box to make the call.
Afterwards, he then crosses the road, gets into his car and continues his onward journey towards Chingford.
That would explain why he knew the name of the flats, but not the names of the roads, why he mentions Chingford, and why he uses the Fulbourne Road phone box instead of the other phone box in Forest Road that would have been less than half the distance to make the call.
That is of course based on the man being an innocent party who just so happens to drive past St David's Court and look up to see the flames up on the 6th floor.
If he was lying about driving, and he was to blame for the fires and/or the murder, then he would have needed to walk from the flats all the way up to the phone box, which would have been risky without a vehicle.
I believe that he had a vehicle regardless of whether he was guilty or innocent. IF the former, then he needed to have parked up somewhere close by. He may have started the fires, then run down and got into a vehicle, which he then drove north up Fulbourne Road, but as he approached the phone box, he gets out and makes the 999 call so that he isn't responsible for being a mass murderer from the whole building going up in flames.
So when he says that he was driving, I think that's true whether he was involved with starting the fires or not.
Interesting to note that the phone box was located directly outside a building called Cedar Wood House, which at the time and up until circa 2019, was a building that dealt with social housing and homelessness for the local area. It could be implied that the man who made the 999 call may have been familiar with the fact there was a phone box located there.
Cedar Wood House closed circa 2020, but is still there today
Interesting also that the phone box (as well as the one in Forest Road) were both removed sometime between late 2020 to early 2021.
if you look on Google street view, and look at previous dates, it takes you back to as early as 2008. When you scroll through the dates in reverse chronological order, you will see a timeline of the area that really builds a picture of the location. You can also see how the flats have changed since 2008.
You can also observe a CCTV camera on the external wall of the building that faces the door. It is easy to circumvent around to the back of the building and enter Parkstone road, without needing to use the main road.