Amending a Large Plan Form 5500

I have to amend a Schedule D attached to a large plan 5500 that was just filed for 2021.  The employer neglected to give me a new participating plan.  

Do I just attached the updated Schedule D to the 5500 for filing or do all the Schedules and original documents get refiled as well?  The 5500 Instructions are not clear.

I got the following from the EFAST2 FAQ...

Q4: How can I submit a delinquent or amended filing?
The Form 5500 Series Version Selection Tool will help you determine which version of the Form 5500,5500-SF, or 5500-EZ you should use. Refer to the form-specific instructions for more information on filing requirements. An amended filing should be submitted as a complete replacement of the previously-submitted filing. You will need to resubmit the entire form, with all required schedules and attachments, through EFAST2. You cannot submit just the parts of the filing that are being amended.

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