After picking the new sig I want(the blue one) the screen refreshes and the end result is as below. The new sig is on top while the old sig(the black one) is on bottom because it is still on their server.
I then hit ctrl + f5 (not 5 incase you did that) and the final result is a forced server refresh and it now shows the blue sig on the top and bottom.
All else fails if you like I will log onto your hwbot and have a go at it. Let me know.