Stopwatch/Timer?

[Rigorous]

i'm looking for some way to (most preferably) send a message to MSBT or start a bar timer (less preferable) when my "/castsequence" is reset by the use of, at least, a time argument, or at best, any argument, for the reset modifier (i.e. "reset=30/combat/target").

or, more simply, is the information designating the reset of the castsequence available to the UI allowing a notification to be sent for any reset condition being met or is there any way to definitively determine that information indirectly?