Referral rewards stop being accrued only to the referral who did not renew the subscription. There are no restrictions imposed on other referrals, including those higher up in the network.
More information:
If someone doesn't renew the subscription, they will no longer receive earnings from all of their friends, but the entire list of their friends at all available levels is preserved and continues to grow.
Referral rewards will continue to accrue from the moment the subscription is activated.
All higher-level referrals, as long as their subscription is valid, continue to receive rewards from the friends of the referral who did not renew their subscription.