The second and all ongoing issues are much more simple than the first issue of a new publication, as there was a fair bit of setup involved. All you will need to do for these issues is upload your print ready, high res PDF's to PAC http://pac.realviewtechnologies.com/. They will be processed automatically and you can make the issues live once they come through production and you are ready to go.
The following link outlines how to upload a new issue:
http://support.realviewdigital.com/support/solutions/articles/53461-how-to-upload-a-new-issue
Then this link shows you how to make an issue live:
http://support.realviewdigital.com/support/solutions/articles/100062-how-to-make-an-issue-live
If you have any further questions, please feel free to ask.