Skip Frame Q

So…

I have a page which has an intro animation which lasts 314 frames and finishes with a button. When you click the button it takes you to a separate html page with a scrolling photogallery. When I click the ‘back’ button in the photogallery it takes me back to the first html page with the intro animation.

How do I make sure that when I click the back button it skips the first 314 frames (bearing in mind I am returning from a separate html page)?

Whoever answers this is a total star…