Yes! You can have multiple Dronelink accounts associated with the same user profile. Make sure you are logged in when you sign up for the second account, and Dronelink will automatically associate the new account with your existing user profile. The web and native apps allow you to easily switch between each account under the same user profile without having to logout and login again.
Having multiple accounts is particularly useful if you fly for fun and for business. You can fly all of your recreational missions under your Hobbyist account (one-time charge, no metered usage) and then fly all of your commercial missions under your Professional account (recurring charges, metered usage).