Comparing two Joda-Time DateTime objects

isAfter and isBefore methods compare dates by millis (ignoring time zone).

In your example, the dates have equal millis.

System.out.println(londonDT.getMillis() == estDT.getMillis());  

will print true.

Expressions

londonDT.isBefore(estDT) 
londonDT.isAfter(estDT)

are equal to

londonDT.getMillis() < estDT.getMillis()  
londonDT.getMillis() > estDT.getMillis()