Finally got around to troubleshooting. Swapped out the Ecu for another one and it seems to have solved the problem.
A few interesting observations on sensor readingswith the new Ecu:
1. Spark advance seems to be fluctuating far less on idle
2. Knock sensor readings fluctuate more. The Ecu isn’t dropping out when knock is detected
3. The target afr is now 14.7, previously if fluctuated between 12.5-13.9
Car is much crisper to drive and feels like it has more power (in addition to not cutting out any more).