Answered this myself:
AFI 11-403
3.3.2.3. The ROBD should be used for all refresher aircrew whose aircraft oxygen systems and emergency procedures are not adequately represented in the altitude chamber. Examples include: CV-22, B-2, B-1, F-22A, and the F-35.
3.3.2.4. For all other aircrew, a ROBD is an approved replacement for the altitude chamber during refresher training as long as the appropriate oxygen system configuration is available and the training scenarios are appropriate for their MDS. Trainees will receive ROBD flight pre-brief and post-briefings prior to and following the training system event.