Vip tier annual calculation

Merchant would like the VIP tier system to reset customers’ point balances to zero at the start of each year. However, instead of resetting the customer’s VIP tier to the default (lowest) level, the system should downgrade the VIP tier by only one level.

For example, if a customer has earned 400 points and is currently at the “Gold” tier, after the annual points reset, their tier should be lowered by just one level to “Silver” — not reset all the way down to the default “Bronze” tier.

This approach encourages continued engagement while providing a fair tier downgrade mechanism.