There is plans and work being done to email when beacons are low.
Till then, perhaps we can make worth someone’s time to let others know if their beacon is near expiration? I’ll start the trend by offering a gratuity tip to the first person that informs me of an expired or soon to expire beacon. @Xaldafax notified me of a low beacon on a plot worth about 350k prestige, I’ll tip him about 350c next time I see him for his service! (1% of plot prestige value)