First confirm every cue is late by the same amount
Spot-check one cue near the start, one in the middle and one at the end. If all three are late by roughly the same amount, it is a uniform offset, and one shift step fixes it. If the start is correct and the drift grows toward the end, that is a different problem — see subtitles getting more and more out of sync.
What to enter: negative to advance, positive to delay
In the timing editor, add a Shift all step and enter the offset in the value box: subtitles running late take a negative number to pull them earlier; running early takes a positive number to push them later. If the subtitles are 1.5 seconds late, enter -1.5 — the unit is seconds.
Run it and check the first cue
After applying, the result panel lists each cue's original and new times side by side. Check the first cue first: does the new start time land on the frame where the line is spoken? Then spot-check one in the middle. Every cue moves by the same amount and keeps its own duration.
Export
Once the spot-check looks right, download directly. The output format defaults to the input format and can be switched to something else. The change touches only times — not a single character of text.