I reside in Brisbane, Australia, which does not observe daylight saving time and remains consistently at UTC+10. In contrast, Sydney observes daylight saving, shifting from UTC+10 during April to October, to UTC+11 between October and April.

Earlier in 2025, I transitioned to using Tapo P100 smart plugs to manage my aquarium equipment. I initially assumed the scheduling functionality would align with my mobile device’s timezone settings. However, I’ve discovered that the P100 devices rely on an internal timezone database. The Device Info indicates the timezone is set to Australia/Sydney, and unfortunately, this setting is locked and cannot be modified.

Until the weekend of October 4th–5th, everything functioned as expected, since both Brisbane and Sydney were aligned at UTC+10. With Sydney now observing daylight saving and shifting to UTC+11, all scheduled timers on my devices are now offset by one hour. This discrepancy has disrupted the carefully calibrated balance of CO₂, O₂, and lighting in my aquarium system. To workaround this, I’ve adjusted all schedules forward by one hour, but will need to revert them again in April.

Given TP-Link’s reputation and the sophistication of its products, I would expect support for Brisbane’s timezone to be available. If there is a way to configure the devices to reflect Brisbane’s timezone accurately, I would greatly appreciate your guidance.