Bleary-eyed Australian commuters confused by the dark turned out to be victims of a bug in local cellphone towers.

Local radio stations reported numerous calls from drivers in Brisbane wondering why traffic was busier than usual before the traditional rush hour. Meanwhile coffee shops reported customers who seemed less amplified than normal, while one radio reporter admitted being baffled that his journey to work was in darker conditions than normal and arriving to find his office still locked.

It turned out that those affected had been relying on both the time display and alarm on their cellphones. The problem affected people on multiple networks, suggesting the issue was with time signals from cellphone towers.

At the moment the most credible explanation is that a software bug had caused the tower systems to switch to daylight savings time. (It’s currently summer in Australia.) Brisbane is in the state of Queensland (pictured) which, unlike most of Australia, opts out of daylight savings time and keeps the same time all year round.

The BBC notes that cellphone networks were quick to react on social media. Optus offered to cover the cost of a cup of coffee for customers who showed their phones in a specified city center cafe. Meanwhile Virgin offered to donate cash for one meal for vulnerable people through charity for each customer who posted a picture of themselves with their unexpectedly-early morning drink.