Thanks for your reply.
I have read through those posts and I don’t know if this is the same issue. I tried to used the code by Kiran (slightly modified to use +10 instead of +1) but I doesn’t seem to solve the issue.
The timezone is set to Sydney time which never UTC+9. It is usually +10 and changes to +11 between Oct and Jul.
When I’m logged in to a subscriber account the default is set +10 which is correct but when I login to any of the admin accounts and use the front end to add a listing it defaults to +9 and I have to remind everyone to change the default timezone when adding business hours.
Is there anything I can do to fix this issue? I’m planning to hide the option to change the timezone but I can’t hide it if the admins will need to be able to change it whenever they use the front end.