I found it very interesting your information on Jewishness.org that;
Re surname Elin, saw web reference some time ago (and now maddeningly unable
to find) linking surname Elin to village/shtetl of Elna (spelling variants
Because my great grand father was born in village/shtetl of Elna,, and I found adoçamento of the family saying ELIN. and I thought it was related to patronymic,,,,!,,
Could you please tell me where did you get this important information from?
Looking forward to hear from you,