The most recent 7-day average is also inaccurate, as it is also a partial-week. No matter what average is used, one should always consult the second-most recent datum.
It is a rolling 7 day average. There is no such thing as a partial week. At 23:59:59 on Tuesday the 7 day average will still be a full week (from Wednesday through Tuesday).
To the OP the point about Easter weekend is important. We have seen our volume decline significantly as well. It is a long weekend, many people taking time off to spend time at family gatherings. Any major holiday is going to distort the data compared to "normal" weeks.