When one defines a variable and assigns a datetime object to it, the UI displays the timestamp in UTC. This behaviour applies to all variables which are not defined in the taxonomy.
Obviously the UI recognizes the datetime value, because it displays a "human readable" string. To provide a consistent representation of datatypes, BMC Discovery should display any timestamp in local timezone.
We've written a little TPL module that discovers certificates on windows systems. We've defined two variables, "not_before" and "not_after". The value of these variables is represented by a datetime object. In the UI the variables are displayed like this:
But what it should look like is this: