Although the rank of Nubuwwa (prophethood) has been sealed, one of its elements, namely the station of Indhar or Tahdhir remains. That is the rank of being a Nadhir (warner, harbinger, oracle), a divinely-appointed status.
Likewise, the rank of al-Sidq, or that of being a Siddiq, is the highest station after Nubuwwa itself. The Holy Qur’an describes Mary mother of Jesus as having been granted this rank (Sura 5: 75). It too is one of the elements of Nubuwwa, which is why Prophets like Idris, Abraham and Joseph are described as being Siddiq in the Holy Qur’an. From this Umma, the most prominent example of a Siddiq is the Prophet's most senior disciple and his first successor, sayyidina Abu Bakr (Allah be pleased with him).
Regarding the description of these ranks and the possibility of attaining them, Shaikh Abdul Qadir al-Jilani (rahimahullah) said:
والرجل الرابع : المدعو في الملكوت بالعظيم كما جاء في الحديث عن النبي صلى الله عليه وسلم : (من تعلم ، وعلم ، وعمل ، دعي في الملكوت عظيماً). وهو العالم بالله عزَّ وجلَّ وآياته، استودع الله عزَّ وجلَّ قلبه غرائب علمه، وأطلعه على أسرار طواها عن غيره، واصطفاه واجتباه وجذبه إليه ورقاه، وإلى باب قربه هداه، وشرح صدره لقبول تلك الأسرار والعلوم، وجعله جهبذا وداعياً للعباد ونذيرا لهم وحجة فيهم، هادياً مهدياً شافعاً مشفعاً صادقاً صديقاً، بدلاً لرسله وأنبيائه عليهم صلواته وسلامه وتحياته وبركاته. فهذه هي الغاية القصوى في بني آدم، لا منزلة فوق منزلته إلا النبوّة، فعليك به وأحذر أن تخالفه وتنافره وتجانبه وتعاديه وتترك القبول منه والرجوع إلى نصيحته وقوله، فإن السلامة فيما يقول عنده، والهلاك والضلال عند غيره إلا من يوفقه الله عزَّ وجلَّ ويمده بالسداد والرحمة
Translation: The fourth kind of man is one who is invited to the world invisible, clothed in dignity, as it is related in the tradition: “Whoever learns and acts upon his learning and imparts it to others is invited to the world invisible and made great.” Such a man is possessed of the knowledge of God and His sign and his heart is made the repository of the rare things of His knowledge and He intimates to him such secrets as He has kept hidden from others, and He has selected him and drawn him towards Himself, and guided him and raised him towards Himself, and expanded his heart for the acceptance of these secrets and points of knowledge, and made him a worker in His cause and are inviter of God’s servants to the path of virtue, and a warner against the chastisement of evil deeds [Nadheer] and an argument of God in their midst, a guide and a rightly-guided man, an intercessor and one whose intercession has been accepted, a truthful man and one who verifies the truth of others [Siddeeq], a deputy of God’s prophets and messengers, may the blessings of God be on them. So this man is the end and culminating point of mankind and there is no station above this, except that of prophethood. It is your duty to beware that you do not oppose such a man and be averse to him and avoid accepting him; and be attentive towards what he says and admonishes. So, verily, safety lies in what such a man says and also in his company, and destruction and misguidance be in what is besides him; except such men to whom God gives power and assistance towards truth and mercy.
Reference: Futuh-al-Ghaib p.80 (Discourse #33)