I have. So many I’d like to send you but this one is first! Both were taken at the same time. That looks like a classic anvil shaped storm to me but is there a name for the sky shadows it cast?
Ooh, the colours here are so pretty!!
If there is any word for the shadow, I dont know it and couldn't find it. But, I can say it's casting the shadow not on the sky itself, but on a cirrostratus cloud!
The first image has cirrostratus, cumulonimbus incus mammatus - you can see some slight round shapes on the underneath of the anvil head - and cumulus fractus clouds.
The second image has cirrostratus clouds, which I'm very tempted to call fibratus radiatus, but it looks like shapes are only caused by shadow, so I'll hold off on that.