Two 30 character EAMs from "mainsail," at 23:09z and 23:15z. Not used to hearing Mainsail as an EAM identifier, an identifier usually used when armed services aircraft is hailing any groundstation, which then identifies themselves by specific location (often Andrews, P.R. etc). Last I was listening EAMS were typically accompanied by a specific base identifier, as opposed to "mainsail" which is, I assume, intentionally vague.
As if to highlight this change, AX997 came on at 23:12 to hail mainsail for radio check. When answered by "mainsail," they inquired x2 "what's your station?" To this they were answered "cannot give that information over HF." If I'm confused about when ground stations began refusing to identify themselves at least I'm not alone.
Addendum: Ah, I see this change was also noted in a post below. Interesting that they are being more cagey about self-identifying in EAMs and in response to aircraft. I did hear the "mainsail" voice from above slip at least once, and identified their location before transitioning back to mainsail.

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