Many of you have shared with us that you found the hardcoded To Do stage frustrating. You wanted to be able to setup your own workflow stages without us forcing a particular workflow on you.
Message received! We have removed the hardcoded To Do stage.
For those of you that liked having a To Do stage you can follow these steps to get back something similar:
Create a new custom stage called 'To Do'.
Create a filter to get all open issues that are in a milestone (or assigned if you are in assignee mode) and exclude all issues labeled with a stage label (e.g. 'in progress'). Use bulk edit to apply the stage label for the custom 'To Do' stage you created in step 1.
If you need help with the above please contact support.