Izabella Kaminska had mentioned this routing/rerouting of the grain some time ago but I can't locate the link.
TL:dr, if Poland, Hungary and Bulgaria all say no, the grain will still have to go somewhere and probably somewhere that the U.S. or France contests as an export market, meaning droopy prices.
From EuroMaidan, April 16:
Bulgaria considers banning Ukrainian grain imports, Bulgaria’s acting Agriculture Minister Yavor Gechev said.
Bulgaria may become the third European country to ban Ukraine’s grain imports after Poland and Hungary banned imports of grain and other food products from Ukraine following a surge in cheap goods.
Earlier this week, Poland’s Prime Minister’s office announced that Ukraine’s grain imports will be banned in Poland “to protect the Polish agricultural market against destabilization.”
On 16 April 2023, the Hungarian Agriculture Minister announced Hungary would also temporarily ban the import of grain, oil seeds, and other agricultural products from Ukraine....
....MUCH MORE
Here's the latest at Politico.eu retweeted by Ms Kaminska:
Ukraine's farmers played an iconic role in the first weeks of Russia's invasion.
— POLITICOEurope (@POLITICOEurope) April 16, 2023
But now their prodigious grain output is causing some of Kyiv's staunchest allies to waver.
The most striking is Poland.https://t.co/fsH3Z2aNKU
