I wouldn't say "absolutely no way"
But it's true that there is no public exploit for 5.5.0 at the moment.
The hacking team has an exploit for 5.5.0 now, they will release it in one of these conditions :
- The exploit gets patched on a newer version
- They find another exploit
- There is a very high demand in the homebrew community, meaning there are more people who are willing to contribute and make/port homebrew.
- They find some kind of an emunand based solution or a better way to solve firmware updating problem. (a spoofer made by crediar recently can help download game updates without updating firmware which allows online playing on old firmwares, so that's a good step already).
If you are in 5.5.0 and want to use homebrew soon on your wii U, I would suggest you to block auto-updating asap, at least you still got a hope, but there is no guarantee a later version would be exploitable.