Signature varieties of Nepal Pick# 30

In checking my listings on Numista, I have found identifying the notes in Nepal to be among the most difficult. On this 5 rupees page (https://en.numista.com/catalogue/note204112.html) there are multiple ND lines (with different date ranges) identified as having signature 13 varieties. The Pick number is P# 30 but the sub-numbers 30a and 30b with different lengths of serial numbers and signature 13 among the signatures of each sub-number, are not given on the Numista page. The Numista descriptions do not match Bank Note Museum (http://www.banknote.ws/COLLECTION/countries/ASI/NEP/NEP0030.htm) either, which gives different lengths of serial numbers as possible differences.

Is there any way to determine which varieties a collector has since the dates do not appear on the notes? I think the rest of the Numista entries for which I have Nepalese notes can be determined through manipulation of the various sources but the entry for P# 30 seems beyond comprehension.

Will