The core difference
BDD is a pre-discharge claim lane tied to the separation window. Intent to File preserves a potential effective-date marker while you gather evidence for a later claim.
When BDD may fit
BDD may fit when you are still in the 180-to-90-day pre-discharge window and can complete required exams before separation.
When Intent to File may matter
Intent to File may matter when you are outside the BDD window or need more time to gather records before submitting a complete claim.
Planning note
Use the transition timeline to organize deadlines, then confirm current filing rules on VA.gov or with an accredited VSO.