To switch between accounts that you were invited to, simply follow the instructions below.
Swap company accounts
Click on the link in the invitation email to create/login to your account
Click on your Company avatar on the top-left of your dashboard (with the downward arrow)
Select the other Project
After receiving an invitation to StudioBinder from my company, the link takes me to my Project dashboard. Why?
If you created a new account but the link in the email is directing you to your main Projects page, this is because it's currently set to your default. To switch company accounts, just click on your company avatar on the top-left, then select the account that you were invited to.