Hi CM and welcome back.:)
Have you checked out this site? http://theroadback.org/
Sorry I don't have personal experience to share, but you should hear from others who do, so keep checking. In general though, switches between SNRI's and SSRI's are usually pretty smooth
I would advise to follow your doctor's advice, and know that this is your best course of action :)
Wishing you the best with your switch
"Courage is not the abscence of fear, it is feeling afraid and doing it anyway!"
"Worrying does not empty tomorrow of its troubles...it empties today of its strength."
Corrie Ten Boom
Panic Syndrome recovery due to CBT