They've have over 50 years to return - I don't think there's a time limit. Jews, people with at least some Jewish ancestry, and spouses have the right to move to Israel.
Agreed, 100%. My only point is that when people do the Biblical prophecy thing, it's important to call them out and keep them honest when they claim the Jewish peoples are no longer scattered around the earth. There is no measure by which you can claim you've got less than half the things and claim you have them all, even when rounding up.
Also, they have to remember that to be Jewish in Biblical times meant BOTH and ethnic and religious thing, now it does not. A large portion of the Israeli Jews are not religious. Do they count? If so, why so?