Air Sofia did that before the final announcement by the Bulgarian CAA this week.
They either knew what was coming, or couldn't afford not to be flying until a decision was made.
Vega had re-regd one of their aircraft to an ER- reg, under the control of MJL (Jetline Moldova), but I'm not sure if this is still the case and what is happening to the rest of their fleet.
Bright Aviation's fleet has gone back to the Ukraine already.