I'm after a little bit of advice from people who have hopefully used both PHP and .NET

I love my current job; developing web systems using PHP/SQL, and then developing the front end too... the problem is, my job will very likely soon be changing drastically, moving to Sharepoint back end development using .NET

I have experience using different PHP frameworks and would say I'm not pretty proficient at what I do, I have only dabbled in Sharepoint (helping a friend to build a large Sharepoint site) and have very limited of .NET programming, so I am unsure whether I should try to hold out in my current job and hope I am trained in .NET, or whether I should start looking for a PHP job now (I know of one going locally which could be perfect for me)

I'd really appreciate any advice on which route would be best, thank you