Well-known Deobandī scholar, Shaykh Muḥammad Yūsuf Ludhyānwī Shahīd (1932 – 2000), student of Mawlānā Khayr Muḥammad Jālandharī (1895 – 1970) and khalīfah of Shaykh al-Ḥadīth Mawlānā Muḥammad Zakariyyā Kāndhlewī (1898 – 1982), writes:
There were several phases of the Akābir of Deoband.
The first phase is that of Ḥaḍrat Nānotawī, Ḥaḍrat Gangohī, Ḥaḍrat Mawlānā Muḥammad Ya‘qūb Nānotawī (Allāh have mercy on them) and their contemporaries.
The second phase is that of the students of these Akābir, amongst whom Shaykh al-Hind, Ḥaḍrat Mawlānā Khalīl Aḥmad Sahāranpūrī, Ḥaḍrat Ḥakīm al-Ummat Tahānawī (Allāh have mercy on them) and other Akābir are included.
The third phase is that of their students, amongst whom Ḥaḍrat Mawlānā Anwar Shāh Kashmīrī, Mawlānā Sayyid Ḥusayn Aḥmad Madanī, Ḥaḍrat Mawlānā Shabbīr Aḥmad ‘Uthmānī (Allāh have mercy on them) and others are included.
The fourth phase is that of their students amongst whom Mawlānā Muḥammad Yūsuf Bannorī, Ḥaḍrat Mawlānā Muḥammad Shafī‘ Ṣāḥib (Allāh have mercy on them) and their contemporary Akābir are included.
Now, the fifth phase, that of their students, is proceeding.
All Akābir from the second phase signed al-Muhannad ‘ala l-Mufannad. These were the beliefs of the Akābir from the first phase, and the Akābir of the third and fourth phases have continued to be in agreement with them.
Thus, there is consensus of all the Akābir of Deoband on the beliefs incorporated in al-Muhannad.
There is no scope for a Deobandī to deviate from them. Whoever deviates from them is not deserving of being called a “Deobandī”.
(Fatāwā Bayyināt, 1:526-7)
Read al-Muhannad ‘ala l-Mufannad here: https://barelwism.files.wordpress.com/2019/01/muhannad-aqaid-dar-fath.pdf