The Update is avialbe via LG Bridge.
The Stock kdz firmware for LG K8 AS375 is also available for download from LG Server, If you bricked your phone, You can use this firmware to restore your phone back to stock, You can grab it from below links.
Download LG K8 AS375 Stock KDZ firmware;
File size: 1.3G
Please notes that this firmware is used for LG K8 AS375 Model only!
Do not flash this firmware onto other LG K8 Variants.
To restore/unbrick your LG K8 AS375, You need to install LG USB drivers,LG UP DLL for K8 and LG UP Software.
Please let us know if you want to have the LG UP DLL for the LG K8, we can send it to you by email.