Can only replace some runes on corrupted Item

I dont know if it is intended, but on my two socket corrupt sandals I can replace existing sockets with "default" runes like resolve, desert etc. but I cannot replace it with the purple ones like rune of the chase. Is it either intended to be unreplacable after corruption or is it a bug that only specific runes dont work that way

Do you have another Farrul's Rune of the Chase socketed? Since 0.4 it is limited to 1 (per character): Content Update 0.4.0: Item changes