Using & in the Preferred Citation note of Resource Records
does not translate to & in the that text that appears in the PUI. Instead you must use <code>&</code>. In all other ArchivesSpace fields one can just use & without the code tags and the text renders & in the PUI. I think this is a bug because it seems odd that the <code> tags would be required in only one field. I imagine that in the generation of the "Citation" text, which is only partially generated by the Preferred Citation note, that something is happening so that the system no longer recognizes & as code.
Still a bug in v. 2.5.0. I tried to replace the & in the preferred citation and in an archival component's generated citation. It seems like the whole citation generating process might have this issue.
& worked for me during testing with the Preferred Citation note/generated Citation on public side. [Also, just plain ampersand symbol (without the “amp;” modifier) on its own appeared fine in the generated Citation.] Tested as Admin, Archivist.