Flash timing-activity is a one time activity with no periodicity, as opposed to BLE role timing-activities. Hence the flash timing-event is scheduled in any available time left between other timing-events.
To run efficiently with other timing-activities, the Flash API will run in lowest possible priority. Other timing-activities running in higher priority can collide with flash timing-events. Refer Table 1 for details on priority of timing-activities, which is used in case of collision. Flash timing-activity will use higher priority if it has been blocked many times by other timing-activities. Flash timing-activity may not get timing-event at all if other timing-events occupy most of the time and use priority higher than flash timing-activity. To avoid long waiting while using Flash API, flash timing-activity will fail in case it cannot get timing-event before a timeout.