I think that quote is referenced in post 21...with the source cited
Post 21 was mine and the link was to a prior post of mine on FR. The prior post was to a thread referencing The Arizona Conservative:
https://azconservative.org/2019/12/21/ag-says-2nd-amendment-sanctuaries-illegal
The Arizona Conservative described Herring’s words as coming from an advisory opinion he had issued.
I have no reason to doubt the Arizona Conservative but in this era we must always ALWAYS be extra careful to believe that what we read on the internet is fact based in truth.