check here.
https://forum.xda-developers.com/lg-g5/help/nougat-rs988-t3544147/page3
there's a way to flash the update. i don't know why some people claim that LG bridge finds it and that one guy on reddit got an OTA, neither of those worked for me.
https://www.reddit.com/r/lgg5/comments/68u3vu/15gb_ota_update/dh2ttmd/
apparently there is a separate branch of RS988 for something called Brightpoint or BPT that was on a different firmware branch, they were on 10D while we were on 11D. the OP of that reddit post got an OTA and i thought he was bull****ting since the screenshots were for 10H, which would make 0 sense with us being on 11_ already. Anyways, you can flash the kdz onto one of the regular RS988s that were on 11D, i did, it just factory resets everything so backup data