What follows is my provisional translation (in other words, not official or authorized; see here for more) of a Persian letter written on behalf of Shoghi Effendi to a member of the Local Spiritual Assembly of Bombay. The original text can be found in Ganjíniy-i-Ḥudúd va Aḥkám, p. 425.
Concerning the recitation of the Tablet of Visitation, he [the Guardian] has instructed me to write that this applies only to the Báb and Baháʼuʼlláh. It is incumbent upon the friends to gather on both of the nights of Ascension [meaning Baháʼuʼlláh’s and ʻAbduʼl-Bahá’s]; indeed, it is mandatory that they do so. This obligation, however, does not apply to the night of the Ascension of the Greatest Holy Leaf.
A typed version of the complete Persian text of this letter appears below.