Remove / delete / cancel trigger from ubus

Setting a procd_add_raw_trigger() requires a guess-timate of seconds the trigger is active delayed after firing (the debounce value), a highly variable value.

How then to cancel the trigger before after its expiration firing?
N.B. - testing presence / absence of a 'gating' construct, e.g., existence of a .pid, is amateurish, IMNSHO