The Ceiling's Second Messenger: Counting Saturation Predicts a Steepening in the Diffuse Neutrino Spectrum at 3.02e18 eV

Counting saturation's cap E_ind = 3.02e18 eV, pre-registered as a break in the cosmic-ray spectrum in batch 1, is applied to its second messenger: the diffuse neutrino spectrum. The cap sits 0.480 dex above the cosmogenic flux peak landmark (~1e18 eV) and 2.681 dex above the Glashow resonance — no PeV-band feature is predicted, and that fence is printed on the paper's face. The prediction: a steepening of the diffuse neutrino tail within +-0.1 dex of 3.02e18 eV, registered before any diffuse EeV neutrino flux has been detected. The detection budget (SIMULATED, NOT MEASURED, fixed-address Poisson likelihood test as in the cosmic-ray instrument) is honestly weak: marginal at 100 events above 1 EeV in the most generous spectral world (median 2DeltaLL 8.5), grading only at ~300 events (25.5), blind in the pessimistic world. The simulation's first self-check demanded grading at N=100 and failed; the correction is disclosed on the paper's face.