John Calford = Eliza Dovey in 1893 Qld.
It looks like John died in 1938 Brisbane, father Samuel, no mother's name given.
(Check Trove as there are a couple of interesting articles in 1898 about his insolvency - mentions he has only been a baker for 3 years and 5 months.)
I can only see one John Calford in the 1891 UK census and he is a lodger living in Brighton - says he is single, a "porter draper" and born in Brighton - age NK, so that doesn't help much.
The John Calford marrying either Lilly or Harriet in 1881 in Barton Regis (Gloucestershire) as mentioned by Sue should appear in the 1891 census married to one of the women. I can see a William Rogers married to a Harriett born Bitton (Gloucestershire) - unsure if this is the correct couple though as they are a bit older. If it is correct it would indicate that John married Lilly.
I have located a John Calford in the 1881 English census. His father is Samuel and his mother is Sarah. He is aged 16, born in the parish of Bitton and (if I remember correctly) is a shoemaker.
I had a quick look on the Qld immigration indexes but couldn't see John. Do you know when he arrived in Australia? Was he alone?
None of this answers your question, but does point to the 1881 marriage perhaps being the same John. If he did a runner to Australia leaving a wife behind, he is unlikely to have said he was married (but perhaps widowed even if untrue?) when he married Eliza in Qld. Purchasing certificates might be the way to go, however fibs could still have been told.
I found John on the Australian voter lists. Eliza is with him initially, then seems to disappear early 1900s (I did not look thoroughly to trace her movements). I thought she may have died but I found a death for an Eliza Calford in 1938.