moving raspberry canes

[Mairzydotes]

What is the best time to move canes? When all fruiting has finished? Before the frosts?
My poor fruit has fought a losing battle with bindweed all summer, and the ionly solution is to dig them out and replant in a 'clean' area. Then get the Roundup on their previous site.
And if I move them, should I prune at once, or next Spring?
All answers gratefully received.
Mairzydotes