Main thing I have noticed with burr wear was slower rate of grinding. All said and done I have yet to wear any out to the point of feeling the need of absolutely having to replace them.
If you don’t notice any real change in speed/delivery rate or see/feel any rolled over/blunt edges the burrs are likely totally fine. Hilarious that some spend time trying to season burrs, then think there is some magical lifespan and instantly they need to be swapped out. In that case the usefulness is a fairly small window for those going that anal retentive route. Not saying you specifically, just read around at all of the FOMOR on burrs.