So you are still <originalusername> . Are you sure your username is blocked? If so, how? If it was done by PN then perhaps you should raise a ticket, because they should not be sending any mail to your <username> domain if you can't actually get it.
But first, I suggest you try the folloing if you haven't already. Login to the member centre. Go to the Email settings page, Manage My Mail Option, and then to the Spam tab.
Ensure Spam filtering is ON for your username domain, and that the Discard obvious Spam is OFF. I would suggest "Add [-SPAM] to the subject line" is selected, and then Move to Spam Folder is selected. Leave Aggressiveness as 1, and Antivirus Filtering is YES.
Return to the Summary Tab and check that your <username>@ exists as a default mailbox (you can rename this first bit on the maibox tab if you wish - I believe new accounts use firstname@username.plus.com). Also check that postmaster@ is set up as an alias for your default mailbox.
If there are any redirects set up to blackhole@abuse.plus.com for the default mailbox then delete them. Also make sure that Catch All for the Default Mailbox in your <username> domain is OFF.
Any changes you make can apparently take 30 mins or so to take effect, except turning Spam Filtering ON or OFF which can take upto 48 hours to take full effect. Assuming all that works, you could try logging into you default <username> mailbox by webmail. I think (& hope) you will be pleasantly surprised that the IronPort SPAM filtering is working quite well, far better than previous efforts. Ok I know some users are having difficulties, but these are generally related to certain specifics.
If none of that works, you could see if you could set up a redirect for postmaster@username.plus.com to a mailbox you can access, and ensure the rest of @username is blackholed.
Well, I hope that at least some of that may be of help.
