So regardless of how this ends many people are leaving Tumblr for good. People are cleaning out their pages and sharing their other accounts and what sites to find them on.
I have two major suggestions for everyone leaving. (Things I am following when I do)
1. Do not just up and delete you page just clear or private your stuff. This prevents someone else from getting your name preventing people from posing as you. This is very important if you are trying to make money online, plan to make money online, or have a large following who could be scammed into giving a third party money for your work.
2. Regardless of how you clear your account your last/only post needs to be your new contact information. What sites you are going to and which ones you will be using more. Keep this up to date.
You want to do this for future followers or people who will come looking for you later. Not everyone is going to see where you went if you go now (and clear everything) this will give them an opportunity to find you. It will also properly and clearly state your intentions not to upload to Tumblr any longer. That has other advantages I won’t list here.
The unintentional third thing this will do is that it will create a graveyard of abandoned blogs. That will show a statement of how much was lost due to this purge.