Welcome Suica Mobile is available at all times unless otherwise specified. However, the following operations are unavailable at their given times for system maintenance. 
[Suspended times]
*All times are in Japan Standard Time. 
· Registering to use the Welcome Suica Mobile app: 2:00 a.m. to 4:00 a.m.
· Suica top-up: 2:00 a.m. to 4:00 a.m.
· Displaying usage history: 12:50 a.m. to 5:00 a.m.
· Changing/replacing devices: 2:00 a.m. to 4:00 a.m.
· Purchasing discount passes: 11:45 p.m. to 4:00 a.m.
· Refunding discount passes: 11:45 p.m. to 5:00 a.m.