Reader comments on my error map proposal made it clear I mistakenly assumed that most people are familiar with the standard JR station layout.
Basic Station Layout
JR station gate layout has dedicated entrance and exit gates with a few bidirectional gates in the middle to accommodate different rush hour flows. Important transfer point gates between 2 different train company lines, such as Gotanda station transfer gates between the Tokkyu Ikegami and JR East Yamanote lines are exclusively bidirectional.
Look carefully at the bidirectional Asagaya #4 gate closeup and you can see the exit bound reader and display on the lefthand side. Slightly larger steel rimmed barriers separate the gate machines. Gates are numbered from south to north or east to west depending on the orientation.
Based on reader feedback I created two more iPhone X Suica error map proposals for Asagaya and Koenji stations but something doesn’t feel right. This approach doesn’t work: it’s too complex and also sets up the expectation that some gates are guaranteed trouble free which they are not. The iPhone X Suica problem is a iOS 11 software issue that can happen anytime, at any gate. That much is clear from reader experiences. The only thing to do is wait for Apple to fix it.
It’s a dead end so I’ll stop here. If you are interested in iPhone X Suica Problem coverage I created a page for that. New developments and information will be posted there.