The 10 speed di2 Ultegra deurailler is broken and is now obsolete. I am going to change it to the new 11 speed Ultegra deurailler. I am not totally sure how to do this but Im willing to try. I know I will need to find a wheel that will take an 11 speed cassette and an 11 speed chain. I dont think I will need to change the levers. The thing I am not sure about is do I need to change the front deurailler as well? Any help will be appreciated.