Hello Bottleandtap,
Welcome to the Community page,
If you have a look at this link it tells you all about Standard payroll and all you need to know about it. This link here tells you how to rollback/delete the payroll. Once you have deleted/rolled back to as far as you need to go, changed any information you needed and save it then it is just a case of rolling forward/redoing the payruns again to the point you need to be at.
Any Q's please reach back out to us again.