How to update Global Time dynamically via BR

This is an old post so just leaving this here for posterity:

The solve is to update the app property table with the desired values but in doing so you must increment the timestampticks in the SystemTimestamp table so that it breaks the previous cache and refreshes. My understanding is that this is effectively what is happening behind the scenes when the properties are updated manually and is required in order for the UI and substitution variables to be valid. The application properties have a unique Id associated in this table that can be found via SystemTimeStampType.AppProperties.TimeStampId.