Pardon this possibly information-free post... Since Mike Brown published his papers on the possibility of ~10 Mearth mass body beyond ~200 AU, and it was discussed a lot, I imagine now there is sort of a quiet race among astronomers in TNO field to find this thing. IIUC, Mike has his own team in this race which netted many (most?) of recent large TNO discoveries. One thing which would happen if Mike's team would have a preliminary detection candidate of P9, is Mike would stop talking about his P9 work. Discussing not-yet verified object would only reveal it to the "competition"; but talking about his P9 papers as if he still has no hint of discovery would be misleading on the verge of lying... Well. The last post on www.findplanetnine.com from Batygin (Mike's co-author) which was specifically discussing P9 matters is from Since October 10, 2017. There were many posts before that in 2017, but since then, only one additional post, from an undergrad, not a core member of the team. Maybe Mike found something!