Filing prior year immigration return

Does anyone know if the 2015 returns can be efiled in 2017 if the person is an immigrant?

CRA info from a few years ago : If your client had a landed immigrant status here in Canada and S.I.N. # in 2015, return could be Efiled otherwise it would have to be paper filed.

Not landed immigrant then but applied for it now. Got SIN in 2016, starting
with a 9.

@TimParris.
As far as I know any clients’ returns starting with this “temporary” SIN # has to be paper filed as was the case with a few of my clients on a time limited “working visa” here in Canada.
I guess the best approach would be to establish your clients’ immigration status with CRA - in my case, it was a fairly time consuming and lengthy process.
Also if they had foreign income from their original country in 2015/2016, the immigration status will play an important role on personal tax credits eligibility.

I worked through the residency status and it is clearly Canadian due to:

  1. Married a Canadian, and
  2. No income during the year (in or out of Canada), yet
  3. Immigrated after the 183rd day of the year.

I think that I will have them sign both a T183 and a T1 General. If I have to file on paper, I will. They are signing before Feb 20, so I will not have a chance to verify if the return can be transmitted.