To correct this
You cannot bring a firmware under 5.50 (latest at the moment) online. So no you cannot mod online neither can you bring a retail (non jailbroken) PS4 on 4.55 online. The only way you can is by upgrading to latest firmware which means you cannot use the kernel exploit as it is patch. The only thing available is Webkit exploit which is userland only. We need a 5.50 kexploit (Kernel Exploit) then we could go online without it their is no way unless a bypass or something that allows us to go online is created.
Not 100% sure about this but if he finds a 5.50 Kernel Exploit he will not release it until it is patched.
If you dont know he is a known hacker for releasing PS4 exploits. He is also a known for his iOS 10 jailbreak.