Whether the appeal against the insurer's 6 October 2011 letter was admissible
The letter was not a decision on opposition and not even a formal refusal decision, so the appeal was premature and inadmissible.
Under Arts. 56 and 52 LPGA, only decisions on opposition or decisions where opposition is unavailable may be appealed. The challenged letter merely communicated the medical adviser’s negative view and did not have the qualities of an appealable decision.