Because Public Mobile terminated the old reward system, e.g. no monthly autopay ($2) and no loyalty credit.https://productioncommunity.publicmobile.ca/t5/Announcements/Upcoming-Changes-to-our-Old-Rewards-Program/td-p/1154856
I am using $15/ month 3G plan. I can see the options to buy US roaming add-ons and International min add on in my account. So, I think that you can do so in the new $15/ month 4G plan. But, new $15/ month 4G plan is only for new activation.
As I know, downgrade subscription plans will remove your Loyalty Bonus 30GB. Perhaps, you may consider to port out to other providers to have data at a lower price.
