Find and Update Calendar Time Zores O365

Wondering if anyone has a script or can help me with a script

We have a issue where some calendar items are showing in-correctly in outlook when you edit them

If we view in the calendar or owa they look fine

If we edit in OWA they times are correct

But in Outlook the appointment for 9.30am is showing 10.30am

What I found via powershell and ews was

Subject       : Test
StartTimeZone : Central Standard Time
EndTimeZone   : tzone://Microsoft/Utc