Yes.  After you log in to Flowrev, connect to and authorize Flowrev with each company/organization you would like to use Flowrev with.

After your first connection, you can just select the organization to work with in Flowrev.  By default Flowrev will persist the connection across login, and autmatically renew the connection when needed to sync the org data or the schedules.

Note: If you do not want Flowrev to persist your connection across logins, to the the org details page - click on the detais icon on the "ORG|Company" page in the "Organization|Company" row to visit this page, and disable the option to persist connection across logins.

Also, see:   Can multiple Flowrev users access the same organization?