6.2.4 high cpu => lockup => reboot => boot failed

The thing is that after the testing it rebooted and is now in "boot failed" mode.

Where the admin and ssh are not available...

I was looking into buying a new rn314 by the end the summer.

I don't thing that buying one now and swapping drives will make my data accessible?

Is the data recoverable? should I look for an expert and pay him to have a look?
If there is a way to just get data recovered and copy it to external disks ...

I've used the linux command line for a while, but not that experienced to play with btrfs tools and the readynas setup, ...

As far as I can see in the downloaded logs through raidar: no real disk errors to be found except those from april.
btrfs mentions problems. I presume I would need to be able to login to ssh and fix probably the /c with btrfs tools (restore to another external drive or mount -o recovery,ro)

I could login in the tech support mode, but do not know where to start from there.