No, it looks for dates >= Oct 1 of the prior year and less than Jan 1 of the next year, i.e., thru Dec 31.
When doing date or datetime ranges, it's best and most accurate to use less than the next time period rather than <=.
For example:
a smalldatetime in SQL Server is only accurate to 1m. So the latest time in the year is:
12-31-yyyy 23:59:59
a datetime in accurate to 3ms. So the latest time in the year is:
23:59:59.997
for datetime2, it's:
23:59:59.999999 (idk if it's 6 or 7 decimals, but you get the point).
So trying to code <= '12-31-yyyy <end_time>' is very tricky, especially if, say, the column changes to a datetime2 from a datetime.
So, to avoid all such problems, it's easiest to just say:
< Jan-01-yyyy+1