PS3 won't let me update from USB

[JuniorJr]

I've got my REBUG 4.86 on my USB ready to update my PS3, but when I go to System Update, it says 'The latest update data was found. Version 4.85'. I even disabled my internet so it can't update via internet but it's still saying the latest firmware was found and I can't update via USB.

What can I do to stop my PS3 from downloading official firmware and let me update my CFW?

 

[JuniorJr]

Never mind, I just realised I had to turn on system update debug and now I can update my CFW. I'd like to close the thread now that I fixed my problem.