A restore from the second copy, timed

A drill against the offsite copy rather than the primary, which took considerably longer for a reason nobody had costed.

  primary copy      download 4m, decrypt 1m, import 22m
  offsite copy      download 41m, decrypt 1m, import 22m

the difference: the second provider is in a different
region, and the restore host is not.

64 minutes against 27, and the recovery objective was
quoted as "about thirty minutes" — which was true for
the copy that the likely failure modes destroy.

A recovery objective quoted from the fast path is a number for the case that will not happen, which is the general problem with measuring the convenient thing. Sixty-four minutes is the honest figure and it is now the one in the document, alongside a note that a restore host in the second region would halve it and has not been built.