I've verified as eligible the request for Eastern Punjabi Wikisource
[1]. Although the situation is not totally clear, I've been following
previous (2013) verification of the request for Wikiquote in Punjabi
[2].
At least in Wikimedia projects, ISO 639-1 code "pa" is used for
Eastern Punjabi and, in general, requests for unmarked Punjabi
projects are treated as requests for Eastern Punjabi.
I suppose we should send this note to the IETF Task Force for
languages to have the rules synchronized (although I suppose they are
synchronized anyway).
[1] https://meta.wikimedia.org/wiki/Requests_for_new_languages/Wikisource_Easte…
[2] https://meta.wikimedia.org/wiki/Requests_for_new_languages/Wikiquote_Punjabi