Graph getSchedule returns wrong daylight offset in Customized Time Zone

Question

I have been using graph sdk for fetching outlook users’ calendar (organization). The schedule returned seems to he correct except in case when the time zone returned is “Customized Time Zone”.

For every user that has their workingHours time zone coming as “Customized Time Zone”, I’m getting daylightBias property as 0. It doesn’t make sense because daylight bias 0 would not mean a custom time zone but a predefined time zone (windows/iana).

Also, from their outlook profile and comparing the bias from the API, the daylightBias should come as -60 but it is coming as 0.

Is this a known issue?