I'm refreshing this because someone raised the question on the current "Bertsongs" thread of what changes Bert Lloyd may have made to the song.

The answer is, just a few, none of which alters the sense of the song as it is given in Baring-Gould's "Songs of the West," collected from "an elderly man, Edmund Fry," at Lydford in 1887-88.

Only three verbal alterations - modernizations, really - are of any interest. Whereas BG's text addresses the audience as "Sirs," Lloyd has modernized this slightly to "my boys." He also modernizes the "Malaga/ Malago" (wine) of Fry's and earlier texts to "beer."
Fry's final stanza asks the whereabouts of the maidens' "spencers." Lloyd substitutes "feathered hats."

In BG's printing, the girls' "characters" have all been drunk away. In Lloyd's version - and most everyone else's since he recorded it - it's their "maidenheads."

Lloyd traces the song to "Charming Phillis's Garland." The British Library dates this 8pp. pamphlet to "ca1750," and guesses that it was printed in Newcastle. "Charming Phillis's" text is nearly identical to the one Bruce Olson posted on his website from a manuscript of "1740-1750" in the National Library of Scotland.   Though rather different from both Baring-Gould and Lloyd, the garland text contains an extra stanza that puts it beyond all doubt that the maidens...lost their heads in the alehouse.