I moved some out of a container they weren't supposed to be growing in. They were growing in the container for three years with very little care because I kept forgetting they weren't weeds. I used the container for weeds and don't know how the daylily got in it. When I saw two were growing this year, I knew it was time to move them into another container or in the ground before they flower.
They went in the ground and haven't been looking too happy, but knowing how tough and resilient they are, I think they will make it. The leaves are all still green. But if I had to do it again, I'd say earlier in the Spring when it isn't so hot. I've never divided mine in the fall, but some people prefer that time depending which source you read or talk to.