This just reinforces my belief that foreign shipgirls aren't "rescued" like usual but rather "borrowed" from their nations' respective navies. A kind of "strengthening diplomatic ties"/"we're all in this together" kind of thing.
Hellooo! ♪Nice to meet you, I'm Jervis!
*Brightly!*
Ah!
Ah, you're that girl just now!You're that girl who slipped away after the night battle!
(Based on commentary) In the Winter 2018 event, a new Friend Fleet system is introduced where NPC will appear during night battle and attack before your fleet does.
Both Jervis and Tashkent might appear as part of Friend Fleet in their respective maps, even though the Admirals haven't gotten them as drops yet.