But as
@richieb1971 points out, it's something that should be developed to get the most out of the EWR investment.
On the Ipswich angle, I guess it depends on the service pattern; 2tph Oxford to Cambs becomes 1pth Oxford - Stansted and 1 tph Oxford to Ipswich which would replace/supplement the existing 1 tph Ipswich - Cambs (which an ideal world would be 2 tph - 1 stopping only at Bury St Eds and Newmarket and the other all stations, including reopened Cherry Hinton, Fulborn (& Dullingham with housing development). I'd want to redouble Cambs to Newmarket, too.