This codepage and this control line was widely used in fidonet messages long time before any FTS and even FSP about @CHRS were issued, and golded config files for support this codepage were published and used by sysops in our region. Moreover, even now this is the most used codepage for ukrainian language in fidonet, utf-8 for some reasons is not widely used for cyrillic messages.
I do not think I should stop using this codepage only because it was not included in the list of codepages in FTS-5003. More reasonable, CP1125 should be added in the next version of the FTS-5003. Especially because ===