Yeah that’s what I thought (save for ships from Black Sea nations IF their home port is in the Black Sea).
I guess Turkey would have to agree/change the rules re the blockade.
Turns out Russia has a workaround it can use for some vessels (smaller navy ships and maybe submarines) it has a bunch of inland waterways connecting the Baltic Sea, White Sea, Black Sea and Caspian Sea.
Erdogan would only agree if he got something big in exchange?