Deployment time of application vs actual uptime

Hi Guys,

I want to create a dashboard which will show the web application uptime report in percentage but does not include
the deployment time.
Since, when we deploy the application we inform the client for same.

So, is it any way or any idea that we can get only actual uptime excluding the downtime.

Currently,using heartbeat and I am getting application uptime report but it also calculate the downtime duration.