Any soil readings taken the same time or shortly after watering aren't going to be accurate. Always wait a day or two after watering before taking soil readings. They will be the most accurate. As the soil dries out the readings will go up, then take a drop again after the next feeding.
You referring to meter readings?
The Accurate 8 owners' sheet says to take it 30-40 minutes after watering. In any case, if you're talking about meter readings, is the soil moist enough after 2 days to get a good reading?