In ruwiki, infoboxes often go before hatnotes in source code, which results in this on desktop:https://ru.wikipedia.org/w/index.php?title=Истомин,_Константин_Иванович&direction=prev&oldid=96534230
(notice the infobox is on one level with the hatnote). Nothing wrong with this.
After T143139: [EPIC] Move first paragraph <p> above infobox template on small screens & T145216: MobileFormatter should relocate first paragraph ahead of infobox & T150325: Move first paragraph before infobox on stable are done, this results in this on mobile (actual):
So, the hatnote is moved down together with the infobox, while it should be left above the first paragraph (expected):
Right now our hatnotes have dablink & rellink classes, but we can add hatnote for unification reasons if asked for.