what if sensor battery replacement notification fails on an 'instant trigger' sensor?

I have the newest Simplisafe system (SS3?). So far, the keypad and one of my door sensors, which are used the most often, have periodically given me successful "low battery" warnings due to low battery.

But I've had two other window sensors which were set to "silent alert" not alert me - just one day it said they were 'not responding'. While that is also useful, I guess - replacing the batteries fixed them - what happens if there's a low battery on a sensor that is set to instant trigger? Will the alarm instantly trigger because a battery dies, if the system can't identify the problem?