Firmware Version:  SMBT-1.01-35
Date:  2019-08-08
ChangeLog:
    Some optimizations 

Firmware Version:  SMBT-1.01-34
Date:  2018-8-1
ChangeLog:
    1. Enhanced error correcting capability for SIM data
    2. Added feature "Billing Increment(s)" for "use Build-in SIM Server" mode

Firmware Version:  SMBT-1.01-33-2
Date:  2017-12-25
ChangeLog:
    1. Fixed the issue about that enabling SIM SLOT from SIM SERVER is invalid
    2. Optimized compatibility for SIMs

Firmware Version:  SMBT-1.01-33-1
Date:  2017-9-22
ChangeLog:
    1. Enhanced secureity capacity
    2. Fixed a BUG about PIN unlock

Firmware Version:  SMBT-1.01-33
Date:  2017-9-4
ChangeLog:
    1. Compulsively enable "SIM Auto Enable after Changed" feature, and delete this item from configuration page. Any "Disalbe" operating will make the SLOT power off
    2. Judge whether SIM is changed on basis of IMSI
    3. Reset all of statistical data when SIM was changed
    4. If a SLOT is being DISABLED, and it is started without changing a new SIM, it will be power off in 2 seconds
    5. In the case of "Use Build-in SIM Server", the rules will be effective after change without reboot the device