Hello! You can reset your Rewards and disconnect from Uphold, but you will no longer be eligible to earn. You can learn more about that change here: https://brave.com/blog/rewards-changes/
Self-custody BAT payments on Solana is currently available as invite-only to start, but will continue to ramp up. You can find more on this here: https://brave.com/blog/rewards-solana/
Let me know if you have any questions or concerns. Thanks!