This film has been covered several times with the various releases from mountain films. There is the well know scope feature which I believe was not particularly good quality wise, the image was quite soft in places.
From what I have seen of recent years, most of the feature prints are now faded. There were also several 400 and 200ft extracts released of which I have two,

The day of the Triffids, 1 x 400ft colour sound on very good low fade stock, a good sharpe, bright, clear image and very good sound,
Blind Danger, 1 x 400ft colour sound also on the same very good low fade stock.

The above two 400ft releases are the two joined together which make up this 600ft version we have. The two versions have a perfect matching frame, focus and sound level so I assume they came from the same source material, the projector doesn't need any adjustments between the edits.
I did also have two of the 200ft excerpts that were put out but unfortunately, the fade on the 200ft shorts was too much to be able to add to the 400ft versions.
This 600ft reel stands well on its own and makes a good story.
The running order starts from the original feature opening, the pre title scene, the main title, and the meteor shower.
Following the attack by the triffid at Kew Gardens it fades out to black, this is where the "Blind Danger" 400ft fits in perfect and starts with the fade in of Big Ben the next morning where the main character, Bill Mason", wakes and having removed his eye covering discovers everyone is blind. This runs to the end of of the Blind Danger reel with the crashing of the plane into the ship and Bill Mason & Susan escaping, then the last section from the first 400ft is edited back in here and with the last lighthouse scene and the fight with the triffid;
this runs to the end of this scene with the statement from the radio, "There is no one here who can see, there is no one left". The reel ends with an image of the arc de triomphe and the abandoned cars followed by a closing caption card explaining that there is a possible way forward to end the plant invasion.
Ideally, this is where the ending of the feature would be added to complete the film but with the quality of said reel being poor in comparison, I prefer to leave this as the 600 reel it is. The two 200ft releases we had did cover Bill Mason & Coker in France. one reel ran to the end and the escape from the blind home invasion. The other 20ft reel cuts to "Destruction" back at the lighthouse and runs through the melting of triffids with sea water and closing shots of Bill Mason, etc. climbing steps to a church and the end title. Unfortunatly, we ended up selling these tewo reels on rather than have a film that was half decent and half faded.

Hopefully, Barry of Indi 8 will be able to confirm how many 200ft versions were released, or anyone else who may have all of them.

It's nice to see this title in colour Tom, most of the prints I've seen have faded, I think it was a popular release at the time and there used to be copies for sale at every film fair, not so many on offer these days, nice find, Mark