If the reason that you need to delete the 485 is because the patient was discharged prior to the start of new cert period but after the recert visit was completed, then to be able to delete the 485, you can do the following:
Go to Orders tab and click on the drop down to the right of the oasis that generated the new 485. Click on “Change Cert ID” and change to the previous cert. If you are not able to change the cert ID and patient was discharged prior to the start of the new cert, you will need to Void the recert oasis by clicking on the drop down to the right of the oasis and "Unlock and Void Only". You should then be able to click on the pencil in the 485, scroll to the bottom and delete it as long as you haven't already scheduled visits and assigned them on the schedule. If they are assigned, you will need to un-assign them, inactivate any notes attached to them, remove inactivated notes, and then delete the frequencies within the 485. You should then get the delete button.