Premiere Pro 2021 XML shift script
If you load your source files and they are several frames, or even several seconds different than the project expects, you can use this script to align the project with your video file.
Just enter the number of frames you want to shift in the script, and run it on the XML file and it will quickly recalculate all the cuts for you.
 
So for example, if the source video you get is 1 minute longer than the specified source video on BestEdit, and you see that your video has an extra 1 minute intro, you put 24frames*60seconds= 1440 as the value to shift by, and this script will adjust all the cuts and transitions to be 1 minute later on your video.
The easiest way is to scroll through the video until you find a scene change near one of the cuts in the Premiere Pro sequence, then count the time/frames between the scene change in the video and the cut in the Premiere Pro sequence. This won't be exact, you'll have a few frames guesswork, but it should give you a good ballpark of how much to shift.