The BFI used the Giuseppe Rotunno approved master from 2003 or 2004 that was used for the Criterion DVD, too.
The movie is segmented into 4 files on the BFI Blu-ray playing in this order:
00002.M2TS | Time In: 0:00:00.000 | Length: 0:57:25.066
00003.M2TS | Time In: 0:57:25.066 | Length: 0:55:26.114
00012.M2TS | Time In: 1:52:51.181 | Length: 0:01:37.013
00011.M2TS | Time In: 1:54:28.194 | Length: 1:11:00.464
Something went wrong with file 00011.M2TS, because for the last 71 minutes of the film, contrast (or gamma) and color on the Blu-ray aren't correct anymore. The first 114 minutes color and contrast values are the same for the BD and DVD.
Two screenshots to show the differences. The one from the BD is at 123:33 minutes, the one from the Criterion DVD at 124:11 minutes. There's a difference in the length of the movie on both discs because of the Criterion, 20th Century Fox and Titanus logos at the beginning of the Criterion DVD, so the time codes aren't the same.
#1:
BFI Blu-ray
#2:
Criterion DVD
Here are two more screenshots similar to the ones I posted above. They are made with the same codecs and settings. The one from the BFI BD is at 94:08 minutes (it's on the 00003.M2TS file), the one from the Criterion DVD at 94:46 minutes.
#3:
BFI Blu-ray
#4:
Criterion DVD
I checked the BFI BD with three different software players, two different codecs and on my standalone player. The heavy blacks from screenshot #1 are always visible.
Gary Tooze at DVDBeaver praised the disc but now he added a note about this issue. He was made aware of this fault, after I wrote about this at two different DVD forums.