Remember that you are supposed to replace the entire thing because the other components like the sensor or simply capacitors also age. It is a very cheap safety device and simply not worth taking any risks by stretching it to say 15 years instead. The proper way would be to replace them while they were all still fine by making a note in the calendar.
There are two cases:
Your products are faulty and at least one has not made their intended 10 year lifespan. I'd change them all for better ones.
Or
They have reached their lifespan and you only noticed because the first one failed. I'd replace them all.
There are two cases:
Your products are faulty and at least one has not made their intended 10 year lifespan. I'd change them all for better ones.
Or
They have reached their lifespan and you only noticed because the first one failed. I'd replace them all.