Delayed feedback does have a time and a place.
In Fostering the intelligent novice: Learning from errors with metacognitive tutoring, Mathan and Koedinger make the distinction between a novice learner who requires immediate feedback, versus the more advanced learner. For the advanced learner, immediate feedback can be detrimental to the emerging self-correction process.
Many summative evaluations include delayed feedback, which, depending on the learner, is often too late. However, if delayed feedback can be accessed at a later date and used for a transfer of knowledge to the same learning standard or applied to a different learning context, then delayed feedback can be effective, especially for students who have reached a certain level of autonomy.
If reintroducing a learning objective or finding opportunities for a transfer of knowledge, build time into the lesson or activity to revisit posts and feedback in SpacesEDU that covered that learning objective; reactivate this knowledge with a classroom discussion that seeks immediate feedback to ensure that students recall past learning.