That's a good question. UTC is almost certainly still the best candidate even in that case because:
* it's not affected by daylight savings time, which in many candidate timezones causes at least two complex and error fraught time discontinuities every year, and which requires manual intervention at the whims of the US Congress in the USA.
* UTC is the lingua franca of machine time communication -- if you ever have to, e.g., send data about transaction times, server event logs, order histories, etc., to any third party or API, then because there are 23 other timezones besides yours, and data normalization is important, they will almost certainly expect ISO8601 UTC. Yes, ISO8601 has time offsets. No, not all libraries implement them properly on either side.
* The first time you ever have logs from two different timezones -- e.g., a service provider log denominated in UTC and yours in PST -- you will hate computers so much that you will likely quit your job, throw your keys on the floor, and go run a hotdog stand down by the pier rather than deal with it. This is an honest response to time and localization issues but think of your children.
* it's not affected by daylight savings time, which in many candidate timezones causes at least two complex and error fraught time discontinuities every year, and which requires manual intervention at the whims of the US Congress in the USA.
* UTC is the lingua franca of machine time communication -- if you ever have to, e.g., send data about transaction times, server event logs, order histories, etc., to any third party or API, then because there are 23 other timezones besides yours, and data normalization is important, they will almost certainly expect ISO8601 UTC. Yes, ISO8601 has time offsets. No, not all libraries implement them properly on either side.
* The first time you ever have logs from two different timezones -- e.g., a service provider log denominated in UTC and yours in PST -- you will hate computers so much that you will likely quit your job, throw your keys on the floor, and go run a hotdog stand down by the pier rather than deal with it. This is an honest response to time and localization issues but think of your children.