Sorry if I missed the forum message: I think I got mixed up with the workflow today while removing turn restrictions made redundant by the new section of the A5.
The 1963 decree, supported by section A4 of Ministerial Decision DMEO/e/O/1308/1995, states that the southern end of the EO5 starts in Rio. I believe this is still the case, because the ferry still runs for traffic not allowed on the bridge.
I do not think there is an issue with ferries being part of a national road (especially as that ferry was the only route between Rio and Antirrio before the bridge opened).
However, I can accept an alternative tag for ref=* on the ferry route, or leaving the ferry route out of the relation. However, I think the road link between the ferry and the EO8 should be reinstated as part of the EO5, because of the decrees.