The order to complete the CPCA and Core Module requirement is up to you.
Core Modules may be completed at any time during your 4-year cycle. At least one Core Module from each of the four core domain areas are required. Core Modules do count toward your required 60 Class A credits. Although they may be helpful, the Core Modules were not designed as a CPCA preparation tool.
The CPCA must be completed no later than 6 months prior to your credential expiration date. For CRNAs with a 7/31 expiration date the CPCA requirement must be completed by 1/31 of your expiration year.