The "corrected" US mono mix was also the one released as a single around the same time as the album came out; indeed, it may be that extra attention was given to the editing of the track because of its planned release as a single.

The single was exactly the same in the UK as in the US. Clearly only a random mistake caused the earlier mix of the album's first disc to be sent to England for the LP release.

For more information about Dylan's 1965-66 singles, see this page.