modify createdDate

Hello,

I created a section editor for customer testimonials, but i added the records in reverse order.

I entered them going down the existing webpage list, whereas I should have entered them from the bottom of the webpage up.

In other words, I entered the most recent testimonial as the first record in cms builder.

So, now when I add a new testimonial, I have to drag it to the bottom of the record list each time I save it.

Is there a way to reverse the "createdDate" system field data across all records so that a new testimonial createdDate will allow for proper sorting when createdDate is used as a ListPage Field, without doing the dragsort each time?

Thanks