I think I've tracked it down to the culprit : the way OnCalculate handles the rate_totals & prev_calculated. So before discarding calculation I make sure the prev_calculated is up to date with the rate_totals.
EA or Dashboard based on iCustom shouldn't be concerned as long as iCustom from me or Steve were used (they default the updatedelay to 0).
The 15.02 is in observation mode