It's been a while since I paid attention to this stuff, but I remember brecknock hill cheviot farmers being obsessed with getting E3L carcasses... the 21KG dw thing rings a bell too. Having said that, I remember at some point, perhaps during the crash, that a roaring trade with italk picked up, and all the small scotty lambs were being sent to italy... apparently they like a small lamb. Things like that probably through the E3L thing out of whack a little. The post-brexit exchange rate may be doing the same thing now.