When Jack climbs over a table in the cargo bay and does a front-flip off of it, there is a quick cut and actor Tim Ransom is replaced by and obvious stunt double. In addition to the physical dissimilarities, when the scene cuts from the long shot (stunt double) to the close-up (Ransom), Jack's arms are suddenly crossed where they had been down by his sides.
When the group of enhanced individuals is singing scales in the cargo bay, Jack's voice does not match his lip movements. The timbre of his voice also changes noticeably. That is because actor Tim Ransom is tone deaf and could not perform his own singing, or apparently fake it.
After leaving Quark's, Bashir asks Sarina to have a quiet dinner with him the next evening in his quarters. He never actually specifies a time.