Re-reading the Boeing interview, with an alternative more speculative interpretation, is that the AoA sensing issue is fixed, and that the ‘European’ issue of multiple, consequential and coincident alerts for a single failure could be resolved with out resorting to EICAS.
EICAS is a neat (expensive and long timescale) solution with flexibility in display and computing logic, but requires differences training.
The much more difficult technical task is to use the existing (mainly analogue ?) alerting system with some fancy analogue to digital conversion, either embedded logic or an external ‘happy box’ - to provide a sufficient compromise of technical fix and dis-ambiguity, high workload.
The critical point will be if the ‘look alike’ fix will be sufficient to satisfy the tech, authority, and Congressional objections, and although this solution might not be in the stated timescale, can an waiver be granted - a timeline extension only.
If the alternative display-logic is acceptable to other authorities, then a time dispensation is much easier for Congress, particular if other authority's formal acceptance will be subsequent to - later than the FAA.
A lot of closed doors negotiation.
https://informamarkets.turtl.co/stor...sue-1/page/6/1