The escape route from Turkey via the black sea was rarely used in 2013 and 2014 before the so called refugee crisis in Europe reached its peak. Since the recent crackdown on the Aegean Sea route in the last months, more and more people on the run are again trying to move from Turkey via the Black Sea to reach Bulgaria or Romania. Since the beginning of 2017, already 649 migrants were caught, while they were trying to cross via the Black Sea. In addition, the case of 12 migrants, locked on a merchant vessel traveling back and forth between Istanbul and Odessa came to light.
This old new deadly route could be established even more, since of today the Greek Council of State Plenary ruled Turkey as a safe third country, which might increase deportations from the Greek islands. Also today, a vessel with 49 migrants, supposedly traveling towards Bulgaria or Romania, capsized in front of the Turkish coast of Kocaeli. 19 people died, some people are still missing.
Update: The other 5 missing people were dead by the time they were found.