Lidiquity mining rewards are set up using setConcRewards() or setAmbRewards(). In both cases, the rewards are overridden instead of accumulated. Taking setConcRewards() as the example:
Line 69 assigns the new value weeklyReward to the storage mapping. If rewards were already set for this pool, i.e. concRewardPerWeek_[poolIdx][weekFrom] != 0, then the new assignment will override the existing value.
