Beagle - that pass was sold decades ago................
As for the replacement if we go back to the OP quoting Janes " replacing rather than upgrading them might be the most cost-effective option" - note the MIGHT.
I suspect a straight request to upgrade would be throttled at birth by the Treasury so we start by building a campaign that the current airframes are very expensive to maintain (altho everyone else seems to manage OK), then we have to spec & cost a replacement
Oh My GOD!! The Co$t!!!!!!
but we can upgrade them for , well....... almost washers TBH... I mean - reluctantly, we'll accept second best in the National Interest etc etc etc