You’re right, I was really referring to two Farm Events. The first event was scheduled at 18:30 and the second at 18:40. However, due to the way the first event’s sequences currently work (see Nested sequences and Plant Groups) it took 15 minutes instead of the anticipated <10.
But even so, while the second event was scheduled at 18:40, it promptly started working about 20 seconds after the first event completed.