I found this over on NextGen Update (linked above) and it seems promising regarding unbanning PS3 consoles and also anti-ban methods for the PlayStation 3 Console ID and PSN Sign-In.
Here are the details from their site: ANTI BAN+maybe unban: YOU CAN COMPLETELY REMOVE YOUR CONSOLE ID AND SIGN IN.
To do this simply leave second value blank not tested on a banned ps3 yet but it should work+you can hide your console id which can prevent you from getting banned.
First do the PSN Bypass Method: In charles there is a request for a file called auth what it contains is your username, password and console id.
This is what the request file looks like:
x's are just me protecting my info
To get your console id have Charles running with the ssl and all that stuff
Sign in and on charles you will see two new files
Click on https://auth.np.ac.playstation.net
And lastly auth
When you click auth, info should appear on the right click request and you should see your console id to copy it right click on auth and save request then open it and look for consoleid=0000000xxxxxxxxxxxxxxxxxxxxxxxxx00000000 000000000000000000000000
That's your console id to change it go to tools, rewrite and if you have it set up you should already see the stuff to edit the header so click on PS3 3.55 then you should see 2 boxes.
On the bottom box, click add, then where it says type make it body. make sure only request is selected. make the first value is your console id, example the first value would be consoleid=0000000123456789012345678901234500000000 000000000000000000000000
And the second on is the one you want it changed to and where it says "where" make sure request is only selected.
Example of the second value is consoleid=0000000987654321098765432109876500000000 000000000000000000000000
You can only change it to a valid console id, cannot be random or just left blank.
Apparently Sony bans the console ID and if you use charles and send a black console ID you can still sign in and since the console ID doesn't go to sony because you send a blank value they can't ban your number, also some people tried this that were banned from black ops and they were able to play again because thats how black ops had banned was by the console ID but I don't know if this works.. maybe someone that is already banned should try this and post their results.
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