Dear ISP Executive,
If you decide to change your customers email provider from webmail to gmail, can you please let us know? A quick email to let us know we need to change settings on our mail programs makes a lot of sense. Also, if you decide it would be easier to place a notice informing your customers of an email change, it would be smart if you put that notice on the email page.
Thank you, and who should I bill for my past hour of frustration?