Update: Apple released the iOS 11.2.5 Update today, I recommend it for all Apple Pay Suica users.
Apple Pay Suica performance tweaks in iOS 11.2.5 are holding steady in the beta 3 release. JR East also released a special Mobile Suica system maintenance downtime notice today. Major maintenance will be done January 30 from midnight to 4 am. There is also special iPhone only Mobile Suica maintenance scheduled for the early morning hours on January 18.
Maybe it’s nothing but the timing feels like a perfect fit for the official iOS 11.2.5 release: January 18 Japan/January 17 USA