RCIA is the Rite of Christian Initiation of Adults. When it starts varies. Many parishes start around September. Many others have year-round programs so that someone could start any time.
You’ll find lots of discussion about RCIA in the evangelization forum.
There should be a continuous ongoing inquiry process for those wishing to see what it’s about, ask questions, etc.
The Catechetical instruction begins after the Rite of Welcome for those already validly Baptized, and the Rite of Acceptance for those who have never been Baptized.
RCIA even though it has a "instruction (class) component it is really a Liturgical process that will vary with each person.
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