CCDC 2 is the contract behind most of Section 4. Almost every scenario that asks what the architect can certify, who can issue a change, what triggers holdback release, or how a default notice runs is anchored in a CCDC 2 General Condition.
Examitect's ExAC study plan lists CCDC 2 (2020) as a primary reference for six Section 4 categories: types of construction contract, contract award procedures, the architect's role in construction administration, office functions during construction, the architect's role on site, and field functions. That coverage spans the construction phase from bid to warranty.
Even if your IAP experience has been mostly design work, you are practising in projects governed by CCDC 2. The ExAC reflects that: contract clauses are not background reading, they are the answer.