Have you tried the cleaning cycle?
Not that I am advising it. I say that because I have had to replace the baking element in my electric oven 3 times over the last 11 years or so. The last 2 times it lasted about 2 years each time. This is after I started in my bread and pizza baking endeavors. Even though it only costs me less than $20 total to replace it, I decided to see if not using the cleaning cycle will improve the life. I have read that the cleaning cycle decreases oven life span. Don't want to spread any misinformation though, that's just me.
Luckily, I have not had any major disasters on my cordierite stone. It is a little stained, but seems like just the routine scraping with the bench scraper, and wiping down is enough to keep it from giving off any "off flavors". That, along with the long and high temperature preheats and bakes involved with pizza and bread making.