Hard wired Smoke Detector Batteries

When to change the Battery on a wired Smoke Detector??

Googling, I see a range from every 6 months to when it beeps.
Seems if you have had no Electric Outages… every 6 months is overkill. Yet, I do not want the beeping to start in the middle of the night.

I have the Kidde KN-COPE-IC:

We got tired of the hard-wired detectors beeping for no good reason and cut the cord. Replaced them with ten-year lithium battery ones that fit on the same bracket as I remember. That was in 2015 and they still test well, and the one nearest the kitchen lets me know when I’ve screwed up something on the electric range of toaster oven. These are similar to ours, but Amazon no longer carries the exact ones we bought in 2015. There are dozens to choose from, they’ve be absolutely beepless.

Our Smoke Detectors are too high. When they go off we cannot reset them… so I want to be safe.

Seems sill that they need battery replacement when the power is so seldom disrupted. Last time they went off was when the Power went out due to an electrician screwing with the box. We did not know it immediately?? Tough to sleep with it set off.