Redmine

I was using Redmine religiously to track my development and had all kinds of timelines with dependencies set up.

I started falling behind, and eventually, all of my deadlines had passed. I tried changing some, but the dependencies didn't change, so I eventually gave up.
I'm back, a year later, and want to start using Redmine again.

Is there any easy way to just add a certain amount of time to all of the start and end dates for a given project? Or do I just need to write an update to the MySQL database itself?

Thanks,

Chris