The bank can still send $X per week to wherever it wants. So if one loses their key, they would tell the bank to transfer the money in amounts of $X per week t

The bank can still send $X per week to wherever it wants. So if one loses their key, they would tell the bank to transfer the money in amounts of $X per week to a new account. If they have set $X to 2% of their savings, they would have to wait 50 weeks until they can use the full sum again.