Valid From in MDG-F Edition

When we create an edition for a change request of adding a cost center or profit center, valid from date in Edition will pass onto the new cost center/or profit center as a start date of the object.

What will happen if we want to create a change request of changing a cost center desciption text? We do want to keep whatever the original dates on the cost center with the new description text. What we go about valid date in Edition assiciated with the change request?

Thanks

Luo