At SFO a couple of days ago at around 14:00, I was refused entry at all of the following:
Virgin lounge: no entry for PP after 12:45, contrary to what PP app shows (until 14:00) or the SFO electronic info board at the lounge entrance area says (until 15:00), and existing PP guests are kicked out at around 14:30
China Airlines lounge: PP is allowed when no conflict with their contracted airlines flight schedule, so hours vary
Golden Gate Lounge: PP allowed early (8am) or for a couple of hours (between 10ish-12ish) only