It depends upon the type of review done by the propspecive creditor, and thus no one can give you a definite answer except for the creditor doing the approval process.
One simple fact remains, from which you can draw your concludion as to whether to first ditch the AU.
Whenever you have an AU reported to your credit file, your credit score will not be representative of your personal history, and anyone reviewing your score will have no way to back out the effect of any AU on your score.
Some creditors, particularyly when the principal or credit limit requested is small, will save time and $$ by using only your score as an evaluation factor.
Absent any manual review, a solid AU account can be a blessing.
However, as the amount of credit being sought rises, then they are more apt to do a manual review, looking at the innards of your history.
AUs are a great artificial score booster which can help building/rebuilding when score is the primary or only approval ciriterion.
However, if a prospective creditor does a manual review and sees an AU account in your credit report, they may choose to discount or disregard your score in their decisions making since your score is not representative of your own personal history.
Some larger creditors may use their own approval algorithms, and thus the effect of an aritificail AU may not be primary.
Personally, I would ditch the AU and enter into the realm of real approval based on only your own history before doing more apping, once you have reached your apparent stage of building.
Others are sure to have differing opinions, as one cannot predetermine how a given credit will determine their approval criteria.
