A friend of mine in Halesowen had a female Waved Umber in a pot with a split lid and the moth proceeded to oviposit through the split onto the outside of the lid. Presumably they normally choose a crevice in bark etc. and the split lid resembled such a site, or at least was the nearest thing available.
Initially the eggs are a beautiful duck egg blue but soon darken to reddish brown as they develop. Patrick Clement