At the onset of the POSDAO protocol, the 13 original validators (12 +1 unremovable validator) each received 20,000 STAKE tokens as a proactive staking allotment to protect the network. Reward accrual for the original validators began on April 1, 2020 and will continue as long as a validator is active on the network.
Should one of the original validators decide to leave the network, their validator spot will be preserved and the initial 20K allotment kept in the protocol. For security reasons the original 13 validatorships should remain occupied, and the initial 20K allotment cannot be withdrawn. However, an original validator may negotiate to sell their spot to a new validator, and that new validator will then inherit the original 20K staking allotment. Should this validator who replaces the original validator decide to leave, the same parameters will apply.
If an original validator leaves, they are entitled to withdraw all accrued rewards since network inception above and beyond the initial 20K STAKE allotment.
The policy is designed to promote a healthy and viable network and to protect chain security. In the future the terms can be revisited through a governance process; the measure is currently enacted as a safety precaution while the network transitions and successfully functions with public POSDAO.
Note that new validators to the network (those who purchase STAKE and setup validator candidate nodes) are not subject to these rules and can withdraw their validator STAKE as well as any accrued rewards on protocol exit.