will they be known to punters
I think SOU has a core of regular business users (I am a reasonably regular one) and they will be following the airports updates about returning routes, and that core of loyal use will return to some extent.
I think it's sensible that the replacement operators are coming in with a lot less capacity than Flybe had on the core routes taken up so far (although both EZE and LOG on NCL looks a bit questionable), and once we overcome the virus they will start to be taken up.
Ironically I was due to fly with Flybe to BHD tomorrow (booked about 2 weeks before they folded) but first the Customer asked us not to go (due coronovirus concerns) and I ended up cancelling my reservations on the day they went into administration