I've renewed my license increasing the number of PC's, from 1 to 3. This implies a new license key that I've already got, although I haven't introduced it in any PC yet, because I would lose the 62 days my current (old) subscription has left, wouldn't I?

If I had foreseen this problem I would have renewed later but this is what I've done.

The secondary PC for which this increase in the number of PC's was, has lived years w/o ZA so it can wait 62 days more.

My concern is: can I wait that long? Can a license key be activated 2 months (say 60 days) after its purchase?

Alternatively (the "perfect plan"): could I install it now in my main PC only, and get its days of validity added to the old's 62 ones, provided that I don't install it in any other PC during those 62 days (in which case the new key would have to start its life and I'd lose days of the old one)?