@DonaldA the 15 days count down starts from the moment the add-on is added to your account, and the redemption usually just take couple hours. So, maybe redeem it the day before you leave, or earlier if your trip is shorter than 15 days
To redeem login to My Account, click Rewards and then click the link to the rewards portal (or use this direct link to the Rewards portal https://myrewards.publicmobile.ca/ )
Once you are there, click Catalogue, pick the roaming add-on you want to redeem
