There was NO 'revelation' from their GOD to stop polygamy; and there has been NO 'revelation' from their GOD to modify the Word of Wisdom.
Their Second Living Prophet® warned them about the first.
I do not know if there was been any warning about the second or not.
That is only one on my list of LDS beliefs that make no sense.
When I lived in Central NY we used to get quite a few coming door to door. Several challenged me to read their scriptures and "Doctrines and Covenants." So more years ago than I care to recall I sat down with the BOM and read it cover to cover. I put a post it tab on every historical error and contradiction I found.
The next group that came around I asked them about the errors. No explanation was forth coming. They were very polite, but could not defend their beliefs.