14 CFR §450.33

1. (a)An applicant must identify to the Administrator, prior to submitting an application, whether it will submit a modular application for any approval or determination.
2. (b)An applicant using an incremental approach must have the approach approved by the Administrator prior to submitting an application. In reviewing a proposed approach, the Administrator will consider the following:
   1. (1)Whether the modules can be reviewed independently; and
   2. (2)Whether the modules will be submitted in a workable chronological order.
3. (c)The Administrator may make incremental determinations as part of this review process.