recently-surfaced poster for the portland acid test seems to (finally!) pin it as december 29, 1965. https://entertainment.ha.com/itm/music-memorabilia/posters/grateful-dead-1965-can-you-pass-the-acid-test-rare-portland-or-event-poster-w-venue-info-aor-24-/a/7475-26148.s?ic4=GalleryView-Thumbnail-071515
supported by light into ashes' stellar meteorological research, matching memories of driving through snow to get there. https://lostlivedead.blogspot.com/2009/09/north-to-san-francisco-warlocks-in.html?showComment=1536885342285&m=1#c7927659843328029726 #GratefulDead #psychedelic