exchange 2013 - certificate renew question

Hello, 

1. our RapidSSL Certificate will expire.  
2. How to insert the new ALPHA SSL Certificate in the exchange 2013?   (client allready bought it - but I think there is something wrong - certificate name is  9111.customer-domain.com and it links to the IP of the Homepage.  (which is wrong I think).  Ideally the exchange certificate links to the extern exchange server hostname (the public ip)

1. I noticed, that the current RapidSSL Certificate is only visible / binded to Port 443 in  IIS Manager
2. I didn´t see it under Exchange ECP/ECM - Server - Certificate.  (I assume that there are only the local certifcates for outlook 2013)

What do you suggest?

As far as I know - this is the normal way to generate / install a new self signed certificate:

http://www.msblog.eu/exchange-2013-serverzertifikat-erstellen/

Will the iphones, windows phone and android phone will get the new certificate automatically?  (no manually install?) (only deleted account / create account on mobile phone in case it is not working?)

thank you!  Best regards