Thanks to lots of help from Max in Odessa, official clearance was received to sail up into the Danube delta to complete customs and immigration procedures at the port of Vylkove.
Odessa to Vylkove takes three approach days of 25nm, 20nm, 20nm (all into the wind). Long days, but enjoyable, and with a nice expedition feel because this is a very empty coastline indeed. Sensible decision making and adequate water supply is needed.