ADDITIONAL SYSTEM INFORMATION :
issue has been replicated on mac OS X on the following
---------
java 11 2018-09-25
Java(TM) SE Runtime Environment 18.9 (build 11+28)
Java HotSpot(TM) 64-Bit Server VM 18.9 (build 11+28, mixed mode)

------------------------------------------------

openjdk 10.0.2 2018-07-17
OpenJDK Runtime Environment Zulu10.3+5 (build 10.0.2+13)
OpenJDK 64-Bit Server VM Zulu10.3+5 (build 10.0.2+13, mixed mode)

A DESCRIPTION OF THE PROBLEM :
DateTimeFormatter
for symbols "E" and "MMM" in pattern i.e:

DateTimeFormatter.ofPattern("E d MMM yyyy", locale)

Incorrectly adding periods (".") after the short month and day when using the Australia locale en_AU

Expected Output: "Mon 15 Oct 2018"

Actual Output: "Mon. 15 Oct. 2018"


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Locale aus = new Locale.Builder().setLanguage("en").setRegion("AU").build();

DateTimeFormatter dtf = java.time.format.DateTimeFormatter.ofPattern("E d MMM yyyy", aus);

LocalDate date = LocalDate.now();

date.format(dtf);


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
"Mon 15 Oct 2018"
ACTUAL -
"Mon. 15 Oct. 2018"

FREQUENCY : always