Fix a fixed subtitle delay
Use one cue to move every SRT timestamp by the same amount.
Match a clear line
If the same delay appears near both the beginning and the end, select a cue whose speech starts clearly. Enter the time you hear that speech. An original cue at 00:00:10.000 matched to 00:00:08.500 shifts the whole file 1.5 seconds earlier.
Check the first cues
An earlier shift can move a cue before zero. Those cues are flagged in the table. Exclude them or change the anchor before downloading.