I’m trying to establish if the event times that are advertised are in my local time or some other time zone 
Thanks for a pointer here 
Yes, they’re times in your local time zone when you look in Zwift Companion or the game app.
If you’re looking at a website, Facebook, an email or something else, then you need to check what timezone is being advertised.
Hi @Hugo_Sandall,
Thank you for sharing your inquiries about events in the forum! This is Monica from Zwift. As @Steve_Hammatt mentioned, the events are scheduled according to your time zone, based on your device and country. To check the latest events and their timings, please click here.
If you have any other questions or concerns, feel free to reach out to us at support@zwift.com
Hi. The click here link in your post doesn’t seem to be working.