Set custom datetime range based on template variable value

As shown in the pic, i have three variable runId, run start time and run end time. on selecting runId, start and end time values will get loaded. i want to set this time range(start and end time variable) as custom time range values selected in Datepicker. How to achieve it.

Any workaround possible?

Hello how do set your run start time variable and run end time variable to datetime format? Grafana convert aumatically my variable in datetime format to m_sec and can’t resolve it.

Thank you for response !

image
i have this format