Every field is optional and absent or null leaves it unchanged; a list replaces the stored one and an empty list clears it. slackConfigurationIds must be this team's Slack connections, at most 5; emailAddresses at most 20, each a valid address (it need not belong to a Revenium user); dayOfWeek MONDAY to SUNDAY; hourOfDay 0 to 23; timezone an IANA zone. When either switch ends on, at least one Slack channel or address and a timezone are required. Anything else is a 400. Changing a switch, the day, the hour or the zone recomputes nextSendAt and nextAlertAt. Turning the alert on starts it from now, so pull requests already rotting are never announced; lowering the rotting threshold does not announce old ones either. A pull request dismissed or snoozed when the alert goes out is not announced, and neither is one whose snooze covered the moment it crossed, even after that snooze ends; a snooze placed after the crossing silences it only while it lasts. The weekly digest still lists it once it is back in the queue.