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Time-Decision.
149
The eras given for the enthronement of the Acharyas have been calculated from the time of Vikram's coronation;* otherwise, the time given in the said lineage for the establishment of Bhadrabahu II on the Acharya's seat as Vikrama Samvat 4 contradicts the second Prakrit lineage of the Nandisangha; because in that lineage, the mention of Bhadrabahu (II) being 492 years after the Vira Nirvana falls 22 years after the birth of Vikram. The fact that Samvat 22 is not given in the lineage but 4 is given clearly indicates that it is the era of Vikram's reign and began 18 years after his birth. Therefore; if it is correct to consider the prevalent Vikram Samvat not as the era of Vikram's birth but as the era of his reign, and it is also assumed that Vikram was born 470 years after the Vira Nirvana, then the current Vira Nirvana Samvat 2451 will have to be considered 2470; the time of Umasvati will then, based on the said verse, be fixed at Vikrama Samvat 281 or 281, and accordingly the time of Samantabhadra will also be 18 years earlier (around 265 or 265 AD).
There is another opinion regarding the Vikram Samvat, and it advocates the prevalent era as the era of Vikram's death. The main supporter of this opinion is our friend Pandit Nathuramji Premi. You, in the commentary of 'Darsansar', have mentioned your opinion in very clear words and have also tried to substantiate it with some evidence.
* See "Jain Siddhantbhaaskar" Kiran 4, page 78.