We've been developing a mayor update for one of our clients website. Their current website runs EE 2.5. We've made the change to 2.7 for several obvious reasons. And everything worked beautifully on the development server.
Then I noticed that the client hosting is running PHP 5.1. Which is sufficient for EE 2.5. But not for 2.7. Php should be version 5.2.4 or higher. Also, the php upgrade isn't possible without a linux upgrade, so said the hosting company. And that can't be done before the deadline next week.
So my question is, what are the implications of running EE 2.7 on php 5.1?