Why is my AirTag late updating its location?

One possibility: AirTags’ locations are updated when within range of an Apple device that can relay the position; within approximately 10 meters. AirTags that are isolated from the rest of the Apple network and from nearby Apple devices cannot report positioning info.

Also: If you are running iOS 14 with an iPhone 6s, I would encourage updating the iPhone 6s to iOS 15; to the last supported version for that iPhone.

Also AirTags are very low power devices.

They only transmit their beacon intermittently to save power.

Their position is only reported to the FindMy network when (if) that intermittent beacon is received by another nearby iPhone.

I’ve seen nothing official, but anecdotal experiences seem to indicate that the beacon transmits about every 10 minutes; although there may be other governing factors involved as well.

Remember: AirTags are designed to find your objects which are inadvertently misplaced or left-behind. These would therefore generally be non-moving objects.