I had another GRC deposit get stuck and it took them 3 days, what bothers me is that they give no explanation for the delay despite repeated inquiry! The GRC wallet is working properly so the problem is on their end!
My experiences with Poloniex are bad too.
It was my first (and for sure my LAST) trade there and I withdrawed some Qora - but the coins never arrived my wallet. I am waiting now about 5 days for an answer - I created several tickets, but nothing than "we are working" is the result.
Seems they are not interested in customers!