We know it's a pain in the bum to travel and still attempt to fulfill all of your planned/routine work duties. Then once you're finally able to login, you only have limited access to the email platform's navigation? What is this some kind of cruel joke?
In this day and age of data breaches left and right, what you will find with your campaign email account is that if your login is at all suspect, the security features in place will protect your data. This may cause headaches for you, but so would a breach. Perhaps you've called HighRoad Support to have them whitelist your location while traveling, but if you travel often and you're not using 2-Factor Authentication, you will continue to have login woes.
When you access either a hotspot or hotel wireless, each time you initiate a web browsing session, your location will assigned a new IP from the hotspot/hotel wireless IP range. To the system, it looks like your logins are changing locations in mid-session prompting you to either get logged out or only have access to limited options in the navigation. End result: You can't send out your email.
If you have a supported mobile device and would like to avoid this from ever happening to you again, come into the future of secure logins and try 2-Factor authentication. It's basically using an app on your phone to generate a unique login credentials each time you're not able to access your account due to travel.
Kick login troubles to the curb and try 2-Factor. Read more about 2-Factor Authentication.