Unfortunately BioStar 2 does not support daylight saving time yet.
We hope to implement it by version 2.6 at the end of this year or Q1 of next year.
For a temporary solution, please try the following.
1. Sync the devices
This should sync the device time with the changed server's time.
If that doesn't resolve the issue,
2. Stop and restart BioStar 2 service.
This should apply the server PC's time to the BioStar server time.
Sync the devices again in BioStar 2 to confirm that the server's time is applied.If that doesn't resolve the issue try the following,
3. Change the timezone on preference and device.
Go to Setting > Preference and change the timezone to -1 or +1 based on start or end of daylight saving time.
Apply the same for the device