If an arrest is granted, the debtor may arrange for the release of the vessel by putting up security.
Rather than putting up security, the debtor may petition the Court to lift the arrest in summary proceedings, arguing the arrest is unlawful. Although the Court - in such summary proceedings - will anticipate on the likelihood of success in the proceedings on the merits, summary proceedings do not allow a thorough investigation of the allegations made by both parties. It often comes down to the Court weighing the interests of both parties, taking into account the arguments that have been put forward and the facts that summarily have been established.
Summary proceedings may be arranged to take place on (very) short notice. The lifting of an arrest can be effected within hours.