Yeah, I’m reading, doesn’t sound like it is a violation one bit.
https://en.wikipedia.org/wiki/Montreux_Convention_Regarding_the_Regime_of_the_Straits
Ukraine to ask Turkey to close Bosphorus for Russian naval ships
The request is based on the Montreux Convention Regarding the Regime of the Straits, which demands Bosphorus for the ships of the belligerent countries
14:26, 29 November 2018
Read articles 10,11, and 12. Capital ships are prohibited from transit through the Straits unless belonging to states with a Black Sea coastline. So are any and all warship above 15,000 tons. That pretty much rules out any effective NATO presence.