The dialect cache gave a day to every value that says the reasoning
field is refused, and that includes the combined "field refused, reasons
regardless" value, which one answerless reply writes. One reply could
therefore stretch a lesson to a full fresh day, against the rule that a
lesson read from a single reply keeps the hour.
A lesson now says what taught it. A 400 refusal gives a refused field
its day. A reply that upgrades a refused field to the combined value
keeps the refusal's remaining lifetime rather than a new day or the
hour, so the refused request does not come back early either.
Marc-André Bombeck
5dec158c9d