Analyzer 400B add to 400E

I've have about 4 x fortigate 200b, all running 5.2.  But one of them having issues adding to Forti Analyzer 400E, due to code which is on 6.0.2.

I've updated a Analyzer 400B we still have and was hoping to use this as a collector and push the logs to the 400E.

I've enabled log forwarding on the 400B, I'm guessing it is due to code again it's the highest I can go to?

Cheers