LG G Pad X 8.0 on T-Mobile has started to receive December security update. The update weighs around 95.3MB and the software version changes to V52120l.
The update beings December security update, minor software stability and bug fixes. The update will be rolled out in phases, it will take couple of days if the update is not received now.
To check for the update manually, going to Settings > General > About tablet > Update Center > System updates > Check For Update.