There's an announcement on Ahashpool about them changing the unit for "scrypt" to mBTC/Gh/day (from previously mBTC/Mh/day) to match other pools.
Does Awesome Miner need to update for this to keep the calculations correct?
Yes, an update to Awesome Miner will be required. Awesome Miner will have to take the new value and divide by 1000 to get the correct reading.
For some reason, Yiimp pools use the same hash rate unit for display on the web site as in their API's. Preferably the API's should have a fixed unit, but that's not the case. Nicehash also uses that design.