The Sengled bulbs are zigbee but are unrelated to the hue bridge. They are connected directly to HE and use the Advanced Zigbee RGWB bulb driver.
I pointed out the Advanced Hue bridge because of its very high activity in the apps log.
In retrospect, the zigbee overflow might have been because they were not responding due to radio shutdown. So the severe load may have started with that advanced hue bridge.
