If you are travelling across North Africa, you can expect delays as Niger has closed it's airspace.
South African flights badly delayed.
By now, they will have worked out the rerouting and should not be a problem but no telling. I had exactly the same problem in 1990 (I think it was). On a daylight Sabena from JNB to BRU and Algeria closed their airspace when we were almost on their 'doorstep'. Had to travel west and refuel in Casablanca before going north again. So I missed connection to LHR but they put me and others in the hotel.