You can now sign up for LRT right in the Solo Portal. On the dashboard, if you are not already subscribed to LRT, you will see the option to buy a plan for your unit there. Your Solo must be turned on and online in order to see this option in the LRT section of the portal.
Now controls for LRT are moved to the Solo Portal, so you can cancel or change any subscriptions from there. Go to Subscription Info in the upper right hand corner of the portal to find these settings.