Daylight saving time settings

[Yealink_Peter]

Hi Jon,

Thank you for your detailed description.
From my side testing, I try reproducing your problem by upgrading the phone to 6.73.0.50, choose the time zone to "-7 United States-Mountain Time", it did display the long list of items as below image shows, then I try downgrade to 6.73.0.40 and upgrade to 6.73.0.50 again, it also performs normally.
   
I have uploaded a template of DST xml, you can find it defines the same DST rule on "-7 United States-Mountain Time" & "-7 Canada (Edmonton,Calgary).
<DST szTime="-7" szZone="Canada(Edmonton,Calgary)" iType="1" szStart="3/2/7/2" szEnd="11/1/7/2" szOffset="60"/>
<DST szTime="-7" szZone="United States-Mountain Time" iType="1" szStart="3/2/7/2" szEnd="11/1/7/2" szOffset="60"/>
So, please be aware that when the phone complete the upgrading and revert back to idle, you should reset the phone to factory again.

Thank you.
Best Regards,
Peter