I read your article and it's well worth reading. It claims that it's an antique courtesy that a justice retire in the administration of the party that chose him (or her) and within the first two years of a president's term. Wow. Payback by Kennedy, generously. He's 81 and was rumored even last year to be on the edge of retirement.
Ginsberg says she won't while Trump is prez, but she IS 85, and pretty clearly failing right now: my guess is that the matter won't be left to her, but to nature. Soon, soon.