Hi Andrew
I have run into the same issue before, unfortunately, there is no easy way to trigger the generated history. The generate history can be triggered by via the rest API, so you could create a script that monitors the mango PTCP data source, stores the timestamp when it disconnects, then when reconnected, do an API request to start the generate history with the saved time stamp and the reconnected time stamp.
I did not have to go this far when I ran into this issue so I have not attempted the script yet.