Sorry, I can't help with the dummy as DD wouldn't have one, but we kept wrapping til DD was about 10 months! And now, she still has the wrap in bed with her to cuddle should she want to.
We transitioned to a sleeping bag - started off putting her in the bag lying on top of the wrap. Then folded the wrap over each arm IYKWIM. She was able to get her hands out after a while, and now when she lies in her cot on top of the wrap she picks up either side of it herself to hold!