A federal appeals court could determine whether the regime gets to re-arrest Harvard Medical School researcher Kseniia Petrova when her visa expires on Sunday - and possibly stick her on a plane back to her native Russia, where she fears persecution or worse. At issue is an order by Boston federal judge William Young - which he issued shortly after a hearing at 10 this morning  -   ordering the regime to extend her visa and leave her be at least until after the conclusion of her current criminal case over those frozen frog embryos before another Boston federal judge: The Court orders that the petitioner shall not be re-detained for immigration purposes pending further order of this Court or by order of the Judicial Officer in petitioner's federal criminal action. The petitioner shall not be transferred to another district unless the government provides advanced notice of the intended move.…