Analysis of information sources in references of the Wikipedia article "Yulanpen Sutra" in English language version.
This is an index to the Taisho Tripitaka - nb Volume 16 is listed as 經集部 or Collected Sutra Section; it is where Taisho 685 (The Buddha Speaks the Yulanpen Sutra) and Taisho 686 (The Buddha Speaks the Sutra of Offering Bowls to Repay Kindness) are located.
p.302 -Although this sutra has often been regarded as apocryphal [Japanese version has in recent times], the contents and ideas in it are well rooted in India as we have seen above. In addition to that, the vocabulary and usage of Chinese words are more archaic, compared with Kumārajīva's corpus (401-413 CE), while they resemble greatly the translations by Dharmarakṣa (fl. 265?-311 CE). Moreover, the transliteration 鉢和羅 (EH pat γwa la > MC pwât γwâ lâ} of Skt. pravāra(ṇā), which only occurs in this sutra and its adaptation, i.e. the Baoen Fengpen jing 報恩奉盆經 (T. 16, no. 686, 780a20), indicates clearly that this sutra is not apocryphal but a genuine translation, because only somebody who knew the original Indian form was able to transliterate it thus correctly into Chinese. In conclusion, I assume [<-missing in Japanese version] that this sutra is not apocryphal, but a translation from an Indian text translated by Dharmarakṣa or somebody else in pre-Kumārajīva times [Japanese version has 3rd to 4th century CE]. [c.f. p 189 for equivalent in Japanese version] Also c.f. p 301 for derivation of Yulan from Middle Indic (Gandhari) *olana.
Pravāraṇā (Pāli Pavāraṇā) zizi 自恣 and suiyi 隨意 in Chinese, is a ceremony held at the end of the three-month rainy season retreat [also called vassa] by Buddhist monks. In Theravada Buddhism and in Nepal, it was and is still held on the full moon day of the seventh or eight month. i.e. Āśvina (September–October) or Kārttika (October–November) respectively.
