There is no doubt about the time the flight was to take off.
https://www.bbc.co.uk/sport/football/47013474
These messages between Jack McKay and Sala were translated from French.
Friday, 18 January
8:01pm - Sala: "I want to leave tomorrow for Nantes at around 11am and come back on Monday night around 9pm to Cardiff if that is possible."
8:05pm -McKay:"Good. I'll send a message when that's sorted."
Sunday, 20 January
5:00pm - McKay: "Hi there is it possible you could come back at seven in the evening on Monday night? Just because the pilot has to get home in the north after he gets to Cardiff."
5:01pm - Sala:"Hi, Half past seven would be possible."
5:03pm - McKay:"Yes that's good."