When we've had "too many" hens, we've had multiple large salad bowls full of eggs on the countertops. And that's after overwhelming our friends and neighbors.

They will easily last 4-6 weeks with no major degradation (i.e. still good for omelets, but use the freshest ones for poaching).

The forest predators eventually help moderate our egg surplus. Free range comes with risks, alas.

Interesting point about ridge-cracking. I'd never thought about it, but it makes sense and I will mend my ways! :)