There is currently no concrete emission/release schedule for LDO tokens residing in the treasury fund, with emissions voted on by the Lido DAO. More information can be found on this here: The Lido Treasury.
Initial contributors to Lido have a one year lock, followed by a one year vesting period. The one year lock ends in December 2021.
As per a previous article post, Lido intends to distribute the supply of LDO in the treasury fund to help fund ecosystem development where opportunities may arise. All of these distributions will be completely discussed transparently to the community beforehand, utilizing snapshot votes to probe sentiment.