What is the difference between these 2 queries?
The difference is that the first query will include a job like this:

jobId    Audit_CreatedDate
-------  -----------------
1        2015-04-01
1        2015-06-01


The first row would be included in the query, but the second row won't be included. This is because at least one row from that job met the where clause of &lt; May 9th (or is that September 5th? Please use non-regional, unambiguous date literals).

This same job would be excluded from the second query altogether, since the filter is effectively applied on the aggregate, not on individual rows. MAX(date) = June 1st in that case, and so the job is thrown out as a whole, rather than just the rows &gt; May 9.

Which query is right? Who knows? You'll need to give more details about your actual requirements - your current word problem is not explicit enough for me to understand. Not that any user or client could consume 4.3 or 5.3 million rows anyway.