Also, even if we assume that the conception of the twins must have occurred before Anakin turned evil, this doesn’t necessarily invalidate the above timeline. Anakin and his wife could have had the children while she was still unaware of the depth of his dark side, or she could have been injured after the conception and placed in stasis while Anakin desperately sought a method to save her from death (this would be wonderfully poetic considering the events of ESB). Heck, Anakin’s wife could even take a ride on a star cruiser for ten years traveling near the speed of light. The possibilities are endless.