Cathay Pacific Asia Miles - Online check-in for connecting flights

I have a upcoming CX itin involving connecting flights. When the 48 hours window open up for the first flight, am I limited to only check-in for that first flight or can I check-in for both?

you can only check in for the second flight online within 48hrs of that flight.. a little strange i know, but by the time you get to airport, you'll have checked-in online for both