The United Kingdom could not be seen to be directly aiding the Confederates, hence various levels of secrecy were used for this and similar vessels. For example, at the time she was using an assumed name of Nola, a ruse to help avoid the attention of Union forces.
Because the UK couldn't openly aid the Confederacy, they used covert methods for ships involved in this activity.  For example, one ship was disguised by using the name "Nola" to avoid being detected by Union forces.