Macross II is the original sequel to Macross, and features a new cast of characters. The SDF-1 is still around, as is the Minmay Defense used by UN Spacy (the UN's miltary in space). It focuses on a reporter caught in the middle of the action. Since the production did not involve the original Macross creators from Studio Nue, this project has since been considered a parallel world story.
MacrossII is another OAV entry in the ongoing Macross saga.
MacrossII is also a sharp-looking series, particularly given its age.
MacrossII has a lot going for it: Fine art and character designs, impressive action, interesting story and characters, solid acting in the dub, and quality music in a variety of styles.
In official continuity, MacrossII is an offshoot of Macross: The Movie "Do you Remember Love." The movie is not a part of the original Macross time-line, which includes Flashback 2012, Macross Plus and Macross7.
MacrossII is only a few decades into the future of the current Robotech continuity (which includes the optional Novel Continuity and Comic Universe).
To fit it into the MacrossII setting, the SDF-4 is based on all the various incarnations of the Super Dimensional Fortress and Armor 01 and 02 are used on the SDF-4 rather than the adhoc Prometheous and Daedalus submersibles of the SDF-1.