I see your departure time keeps shifting backwards which is not great.
Are you hand baggage only?
The 20:50 departure (BA352) has lots of empty seats at the moment. If the flight you're on is cancelled a brisk walk to the nearest customer service desk or ticket desk in Galleries South should sort you out. ^ BA352 will fill up quickly but has at least 9 seats in J & 9 seats in Y available.
If needed, you may also be able to rebook yourself using the BA App if you have it.