Broadysword - are the burial records that you downloaded available to anyone, and if so where, or did you have to ask for a copy? I haven't found them online (except as below), and the best I could get on the original registers was these entries in the West Yorkshire Archives catalogue:
https://www.catalogue.wyjs.org.uk/CalmView/Record.aspx?src=CalmView.Catalog&id=CC01896bhttps://www.catalogue.wyjs.org.uk/CalmView/Record.aspx?src=CalmView.Catalog&id=CC00122&pos=16(The first link includes a potted history of the chapel, and the second is lists of tombstone schedules, but there won't necessarily be a stone - I think the relevant bit of burial ground has been redeveloped, and it would depend on when the stones were surveyed, if there ever was one.)
I had a bit more success with the Calderdale FHS database. This shows the previous burial as an Elizabeth Barker on 31 Dec 1874, and the next one as Jonas Bairstow on 14 Jan 1875.
In the absence of the original register we can only speculate, but I wonder if it might have had a column for date of death, Isaac possibly died overnight on the 10-11 Jan and the registrar was given one date and the chapel the other, then whoever transcribed the register took the death date rather than the burial date. But as I say, this is just speculation.
However, I tried looking for some of the nearby names in newspaper items. Most of them didn't appear, but I struck lucky with William Saville: the transcript gives his age as 68 and the date of burial as 24 Feb 1875, but the Brighouse News of 27 Feb 1875 gives 24 Feb as his date of death (and same age). So it does rather look as though there may have been some discrepancy in recording, transcribing or labelling the burial data.