My Early Thorn larvae have begun the next stage in their career...bless 'em.
They have started spinning leaves together for protection (pic 1). Another has fixed itself to the outside of the box (pic 2).
I think they would be better off in one of those small plastic fish tanks, but as I haven't got one I hope they survive in their box to emerge as adults. Thirtyfive at last count but some were quite small.