To encourage long-term stability, ndau accounts accrue a bonus Ecosystem Alignment Incentive (EAI) lock incentive if they are locked by the holder to prohibit withdrawals for a specified countdown period. A locked account earns a lock incentive based on the countdown period specified.
Longer lock periods provide larger lock incentives, and the EAI Rate Schedule is published by the Blockchain Policy Council (BPC). The current maximum lock incentive is obtained when an account is locked with a three-year countdown period.
When an account is locked, the holder specifies a countdown period and, optionally, a second account address to which its accrued EAI is to be credited. This alternate address may be unlocked, allowing credited EAI to be transferred while the original account balance remains locked.
While transfers into a locked account are permitted, no ndau may be transferred out of it. When the holder intends to unlock an account, they start the countdown timer for that account in the wallet app. The account’s specified countdown period begins, and no further incoming transfers are permitted: EAI continues to accrue and is still credited to it. When the countdown period expires the account is unlocked, and outgoing transfers are again permitted.
When an account is locked, its Weighted Average Age (WAA) is immediately increased by the length of the countdown period. Its WAA continues to be updated at each incoming transfer until the countdown timer is started. Its WAA is then frozen until the countdown period ends, at which time the account is unlocked and its WAA resumes increasing.
A locked account may be relocked at any time, and the account to which its accrued EAI is credited may optionally be changed when it is relocked. If the countdown timer has not been started, the new countdown period must be longer than the current countdown period. The account’s WAA is immediately reduced by the length of the current countdown period and increased by the length of the new countdown period. If the countdown timer has been started, the new countdown period must be longer than the time remaining before the current countdown period ends. Its WAA is reduced by the remaining length of the current countdown period and increased by the length of the new countdown period. Relocking an account cancels any started countdown timer: the account will not be unlocked until the holder starts the countdown timer again and the new countdown period expires.