Migration of current PHP development to SAAS on YII Framework

I am looking for a developper who can re-design the actual application to Yii Framework because the current PHP framework is not up-to-date anymore and non-supported. We are willing to migrate to a new saas environment which is secure, stable and fast.

So, the project is for longer time an maybe forever(!). I have programmed the software myself, but need more time to sell. So I need a partner to do development.