nx_medbill_nsa.nx

nx_medbill_nsa.nx -- ADV3 of the MEDICAL BILLING & PATIENT ADVOCACY ladder: classify a billing SITUATION to the federal protection that actually applies, then render the matching letter. Routes: 1 = NSA emergency (insured, emergency care from an out-of-network provider: balance billing prohibited, cost sharing limited to in-network) · 2 = NSA facility (insured, non-emergency care from an out-of-network provider AT an in-network facility: same protection) · 3 = PPDR (UNINSURED/self-pay with a Good Faith Estimate, billed substantially in excess -- the federal Patient-Provider Dispute Resolution process, 120-day window from the bill date) · 4 = standard dispute/appeal path (no situation-specific federal shield; use the audit/dispute/appeal organs). The substantially-in-excess THRESHOLD is caller data (federal figure today: $400 = 40000 cents), never hardcoded (#11). Flags bundle (i64 array): [0]=emergency [1]=oon_provider [2]=in_network_facility [3]=insured [4]=has_gfe. FAIL-SAFE: letters go to a caller buffer with placeholders; nothing is ever sent. Deadline math reuses the appeal organ's exact leap-safe civil-days calendar (DRY). license_tier: ORIGINAL