If the only reason you need to log in is to get the address, why don't you text it to yourself or email it to yourself, or save a pdf of the instructions/address/whatever and email that to yourself so you can open that on your phone and not need to log in to their site?
Or have your route mapped and print out the map directions with all the addresses (or send them to your nav system)?
I think sometimes some of you "I'm saving paper" people shoot yourselves in the foot by relying on your technology too much. Because when something like this happens, you're screwed. What if your phone died or the cell tower went down and you couldn't get a signal? Or you dropped the phone in a toilet while checking a restroom? Always have a backup plan! I carry paper, and a laptop (with camera feature) with my own hotspot, and a smart phone (which is a backup for my portable hotspot). And there have been many times I had to rely on my backups. I carry the phone/camera, a regular digital camera, the laptop's camera, and a portable scanner. Overkill? Usually. But I've also never lost a shop because I couldn't do what I needed to do while out on the road. If I'm heading out to do 10 shops 150 miles from home I don't have time to find a library or a Starbucks hotspot or a road map (if my Garmin dies). I carry three ways I can record a shop -- spy pen recorder, regular digital recorder, recorder app on my phone. I carry batteries and charging cords all the time.
I don't think the scheduler will want to hear that you couldn't do the job because you couldn't log in when the simple fix was to have your shop docs printed out before you left the house. If you don't test the sites before you leave to make sure you can use them from your phone, you're really putting yourself at risk.
(I don't like trying to read instructions on a cell phone because it's not efficient dealing with the tiny fonts on a small screen and constant need to enlarge and move the page around to read it all. Paper may be wasteful, but 5 cents worth of paper is better than 10 minutes of wasted time. Maybe when i get a tablet i'll be willing to go paperless.)
Time to build a bigger bridge.