Magnetic-Basis Entanglement Chronoscopy in the Aether Physics Model This preprint develops a ledger-first quantification of attosecond, channel-resolved photoionization time delays in helium using the Aether Physics Model (APM) and Quantum Measurement Units (QMU). The central move is to recast the experimentally extracted group delay (Wigner--Smith / Eisenbud--Wigner--Smith delay) into a dimensionless "delay-count" that is native to QMU primitives:\[N(\varepsilon) \equiv \tau F_q = \frac{1}{2\pi}\frac{d\phi}{d\varepsilon},\qquad\varepsilon \equiv \frac{E}{E_C},\qquadE_C \equiv m_e c^2.\]In this form, attosecond chronoscopy becomes a direct measurement of phase-slope in normalized energy, without requiring SI seconds in the main derivation. The paper then proposes a minimal "Aether-attachment" ansatz for interelectronic coherence and entanglement unfolding. The outgoing photoelectron is modeled as a compact Compton-function excitation whose finite-time linkage to the residual ion is mediated by the magnetic-charge basis and the Aether unit through a photon-action closure of the form\[\mathrm{phtn} = A_u\, {e_\mathrm{emax}}^{2}.\]Using Ledger One closure, written generically as\[A_u \cdot \mathrm{curl} = c^2,\]the photon-action atom closes directly on the QMU primitive set, motivating a magnetic-basis treatment for the attachment/exchange mechanism. A two-channel residual-ion subspace is coupled by a transient linkage\[g(t) = g_0\,e^{-t/\tau_{\mathrm{ent}}}, \qquad t \ge 0,\]producing a second-order, level-repulsion-like phase imprint on the channel difference. A geometric overlap argument fixes the coherence fraction as\[\chi = \zeta\,\alpha,\]where $\alpha$ is interpreted geometrically via scale separation between the electron torus minor radius (classical radius scale $r_e$) and the Bohr organization radius $(\alpha_0)$ through\[\alpha^{2} = \frac{r_e}{\alpha_0}.\]With $\tau_{\mathrm{ent}}$ parameterized on the Bohr-period scale, the resulting contrast delay obeys a falsifiable collapse prediction:\[\Delta N(\varepsilon)\,\delta(\varepsilon)^{2} \approx \mathrm{constant},\qquad\delta(\varepsilon) \equiv \frac{\Delta E}{E_C}.\]Here $\delta(\varepsilon)$ is re-parameterized about a reference $\varepsilon_0$ for numerical stability inside a chosen data window. This "collapse test" is proposed as an immediately checkable diagnostic in channel-resolved TDSE outputs or future streaking/RABBIT experiments: if the Aether-attachment mechanism captures the dominant scaling, plotting $\Delta N\,\delta^{2}$ versus $\varepsilon$ should yield a near-flat curve for fixed dressing conditions. The manuscript anchors the model to a published helium benchmark channel-contrast $\lvert\Delta\tau\rvert \approx 232~\mathrm{as}$, converting this directly into a QMU normalization target $\lvert\Delta N\rvert \approx 2.9\times 10^{4}$ and deriving an explicit constraint algebra for the combined dimensionless prefactor. The narrative is connected to the author's companion APM photoelectric series on photon-action transport, coherence-window quantization, and cardioid photon expansion, which provide additional context for photon-action-mediated exchange. This work is intended as a draft scaffold for targeted falsification: it specifies which measured or simulated quantities are required (channel phases/delays, fitted $\delta(\varepsilon)$), what plots to make (collapse and rescaling checks), and what parameter combinations are constrained by the helium benchmark.