Time zone drop down is greyed out and it's not possible to reconfigure the Time Zone on the DIP-44/64 after installing BVMS 12.1 and enabling UAC.
Step1: Go to Server Manager main Dashboard > Local Server on left panel, then select the time zone on right side:
Step2: Click on "Change time zone..."
Step3: Select the desired option, then select OK
Step4: Go backing to Server Manager main Dashboard, do refresh and new time zone is shown: