Unsealed Spellbook No Quick Cast

When switching summoner spells with Unsealed Spellbook rune spells like ignite and exhaust dont have quick cast by default like your original 2 spells.

Easy to replicate in testing.

(Or was there an option I need to select that says "swapped spells have quick cast"?)

Thanks

EDIT: Just tested in practice tool. I started with quick casts as normal. Swapped for > Retains quick cast Swapped for > Does NOT retain quick cast

Not sure why this happens. Flash has quick cast, but if you swap it then that spell doesn't.