Upgrade Confussion (Stuck on v15c)

I have a Lg G Flex 2 and i recently got it in december and it updated all fine but when i found out this forum people had a higher firmware on there lg flex 2 where as i only have v15c_EUR_XX so is that the newest firmware or is it old and if it is old can any 1 guide me on how to upgrade to latest firmware as i dont know how to use Tot or KDZ method and upgrade usung them methods
Sorry if i sound like a noob i am not fimiliar with Lg firmware and stuff
Any help would be apreciated

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