You would need to decide which take priority I think.
You could separate them on time so trigger 1 fires say [0.4] minutes before the off, trigger two fires at [0.3] minutes before the off but only if trigger one has not fired, and trigger three fires at [0.1] minutes before the off but only if trigger one and trigger two have not fired.
Would this work for you? If not try to decide what logic you would like to apply and describe that, then you can set about (or ask others to) writing the trigger.