How to solve MI 4A Router (Gigabit & Regular, Global Version) 5 GHz not being available issue:
Links:
To get available countries: /api/xqsystem/country_code
To set country: /api/xqsystem/set_country_code?country=SG
Known issue with this fix: Mobile app stops working!
To use Micro SD card as Internal Storage (Enable Adoptable Storage) on a MIUI 11 phone, follow this tutorial:
https://miui.blog/any-devices/steps-enable-adoptable-storage-miui-11-phones/
or https://c.mi.com/thread-2601107-1-0.html
Following this tutorial you will be able to:
Use Micro SD Card as Internal Storage on MIUI 11
Enable Adoptable Storage on a MIUI 11