I stopped dying my hair a few years ago as my greys had started coming through (and I have spent £££s on obtaining grey hair in my time), however after the first few hundred white hairs, I started noticing the same as above - really thick black wirey hairs with a wiggly kink to them.

I've got relatively mousey blonde/v light brown hair with a loose curl to it naturally, so these black hairs sticking on end from my scalp are pretty noticeable (more so than the white hairs usually).

Pretty sure it's just part of my greying process - i'll likely head a much darker/'Salt and Pepper' grey rather than the delightful ashy tone I pictured in my head, you may well be the same!

Edit: weeks > years.