Assuming a 1 point increase in compression, would 1-2 degrees of timing retard at the distributor be sufficient to prevent detonation on a worst case scenario? Or it doesn't work that way? That is with the same camshafts and cam timing (so no changes to dynamic CR) and no access to higher grade fuel. The engine didn't suffer from detonation previously, but consider it was already at the octane/CR limit.
In this case, it would run with the distributor retarded during break-in and until I can get all parts needed to tune it on ethanol, as it's the only readily available high octane fuel.

 

the dynamic compression if it is modified due to the increase in the static, you can buy a tool to hear the sound of the blow (stethoscope) or launch with some GPS timer and chronometre times always in same gear, same speed and same road and adjust the distributor, always leaves a little margin for hot days / track days.