Just keep in mind: "This seven-year period begins on the exam date of the first Step or Step Component passed and ends exactly seven years from that exam date. If you do not pass all required Steps and Step Components within a maximum of seven years, your earliest USMLE passing performance will no longer be valid for ECFMG Certification." Source
No impact if we have gap between Step exams , you need to just prepare well for these exams as competiitve exams needs lots of preparation time and dedication.
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