BTW...I've been going back and forth with CBP on this eAPIS deal. It appears there is no way to make changes via phone. Your only option is to find an internet capable computer. If you can't get to a computer, you can't come to the US. You can designate someone to make submissions for you and you can file weeks and months in advance. I have a company secretary and my wife checked out on eAPIS so that I don't get stuck.
If you have changes to the passenger manifest, you have two options.
*If you have a deletion, you do nothing more than call the local CBP of landing and report the deletion (this is the only exception to the computer rule).
*If you have an addition, you can go online and submit a new manifest with only the new passenger's (and the crew member's) information under the same tail number.
All other changes require an entirely new submission.
EAPIS replaces nothing. You still have to call the local CBP and inform them that you will be arriving. They don't automatically get the manifest. They have to pull the manifest off the computer and they won't know to do that if you don't call. My understanding is that you still have to have Form 178 and the Personal Declaration, even though all the information on the eAPIS is on the 178 and P-Dec. You no longer have to fax the Form 178.
As always, you still have to file a flight plan with the US and activate it before crossing the border. That probably goes without saying, but I threw it in there just in case.
Hope this helps...if anyone has anything else to add, I'd love to hear it. I'm learning new stuff everyday. The tutorial is woefully lacking in information.