First, you can e-mail the GAN team and ask them to send you a list of your formerly active publishers that have not linked their accounts together. You can then send an e-mail to these affiliates to remind them that they will have to re-apply to the affiliate network once they sign up for an AdSense account. If they already have an AdSense account, then they can just automatically re-apply to the program now.
Secondly, you can run a report from last month and compare it to this month and see which publishers had links up opposed to those that have them up now. De-dup the list and you will find out who is no longer an active publisher. Send an e-mail to these publishers and walk them through the process of getting set back up.
For more information on this change please check out Google’s help page.
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