That is rather a problem - so how do we increase capacity on the approaches? I don't see room for much more infrastructure, so is this an ECTS2 Magic point?
Which begs a whole series of questions about WAML service provision going forwards....
ETCS Level 2 does nothing for capacity. Yes trains can run closer together, but it doesn’t help with junction conflicts, station dwells, etc which are the key determinants of capacity on busy urban railways. Level crossings are also a constraint which is a particular issue in Anglia.
ATO does help, but only at the margins. Consistency of driving can squeeze perhaps 10% extra capacity out, more if it’s a simple railway with short trains (eg Victoria line).
WAML service provision is basically going to be the same until someone decides to fund the construction of additional tracks. The timetable is optimised to balance journey times, frequency, and station calls from all points on the route. If you try to improve any element, e.g. journey times from Stansted, or extra calls in Enfield, or more trains from Hertford, someone loses out in journey time / frequency terms. It’s not BR anymore, and no-one (politically) is willing to see any significant ‘losers’.