Prior notification of an event start

Looking for advice to trigger events before the start of a calendar item. Current experience with GCal3 makes me think I have to roll my own in either Lua or PLEG, but want to see if anyone has already done this.

I work widely varying shifts, and would like to trigger events 1 hour and 15 minutes before the start time. So far my best bet seems to be to use PLEG to run a script regularly checking whether the next calendar entry will occur, and sleeping until the period before.

Has anyone done this and have any suggestions or example code?

Thanks!

StartDelta and EndDelta are your friends …