0 sth that leads to or introduces a more important thing -- prélude [ masculine ]
1 an event etc that goes before, and acts as an introduction to, something. -- prélude
2 a piece of music played as an introduction to the main piece. -- prélude
What that means in terms of the work programme is that it ought to have been the prelude to a final spurt, aiming high and promising speed.
This is intended as a kind of prelude to what will happen after full membership.