Yes, that may very well be true, because speaking from my own experience - I have applied through EE while my spouse is a PR already. I selected no to "spouse accompanying" question and attached an LOE, as was suggested to me (above by Delpiero07) and applied.
Got my AOR - however initially, my application showed me as a primary applicant and my spouse as a secondary applicant. I later got an ADR asking for my spouses medical to which we wrote to them and informed them that my spouse is already there, and subsequently the application was updated and secondary applicant field was removed (hence, leaving only me as a primary applicant).