flower
I don't know. My technical knowledge is wanting when it comes to aircraft and runway lengths.
I have expressed doubts both in these forums and in correspondence with the airport (based on BRS's lack of transatlantic charter flights compared to other neighbouring airports). The airport has assured me that a 757 could make New York out of BRS and the runway length would not be an issue.
The fact that CO and AA appear to have gone into an in-depth study suggests that they are confident too. I assume they could easily have detected a runway problem at an early stage and not wasted further time.
I cannot see the runway being extended in the forseeable future, if ever - too political by far and the gain would be limited anyway.
Air 2000 757s have flown regularly non stop to Banjul (an hour or so shorter than New York but in charter configuration with more pax than a sched operator), and this last winter an Astraeus 737-700 did so each week.
If the EWR service does not materialise now the BRS management is going to have a bit of egg on face having gone so confidently public about the chances this week.