The free Add-on will have the same validity as your current plan. For example, if your current plan expires in 10 days, the free Add-on will also expire in 10 days. You will have to acknowledge this when you claim a reward. Thus, we advise you to redeem your rewards at the start of your plan cycle.
The free Roaming Pass works in the same way as a pre-purchased Roaming Pass. It will be activated based on your first use of Data/Voice/SMS while overseas. If it remained unused, the Pass will expire after 30 days.