It's not possible yet to change your email address in your Pitch account. But as a workaround, you can move your presentations to a new account using your new email.
Login to your old email account and invite your new email address to your existing workspace in the Members section.
After that, move all the presentations in your private folder to team folders.
Then, login with your new email and accept the invitation, and create a new Pitch account. There are a few options, but choose the one that works best for you. You can join the workspace once your account is created.
Once in the workspace with your new account, find the private presentations that have been moved to team folders and move them to your new account's private folders.
After all the presentations have been moved, log back in with your old account and change the owner of the workspace to your new address (it's located in the Members section as well).
And lastly, if you'd like to remove your old address, you can also do that in the Members page!
We're aware that changing your email is a helpful feature. Check out the feature request page here to follow along with updates!