请问i-140 批了，能不能再要求回到pending （孩子over21）？

The portion of the I-140 application was not accurate as I understand now, however it is approved recently. Is it possible to ask for correction and thus let the case pending?  

Also, I have two approved I-140 now, can the pending time of the previous I-140 be added for reducing child’s age when filing i-485?

Those are unusual questions. Thanks for comments or directions.