Cache-hit EAGLE/NextN draft was falling back to full materialization while the target path used page-aligned prefix materialize plus fresh current-suffix splice. That creates a target/draft KV source asymmetry exactly on the high-cache-hit path where decode accept length collapsed. The draft model still does not get next-layer async prefetch; only the same-layer current suffix compose contract is made role-agnostic.
Constraint: EAGLE/NextN has no real next decoder layer, so draft async prefetch remains disabled.
Rejected: Restore draft full-materialize fallback | recreates the observed target/draft cache-hit asymmetry and hides stale-current-suffix bugs.
Confidence: medium
Scope-risk: moderate
Directive: Do not reintroduce draft cache-hit current-reuse fallback without proving the draft persistent pool has fully fresh suffix rows before attention.
Tested: Local py_compile for cp_shared_kv_runtime.py and test_cp_shared_kv_runtime.py.
Tested: Remote g0034 container py_compile for changed runtime/test files.
Tested: Remote g0034 pytest test_cp_shared_kv_runtime.py: 73 passed, 5 warnings, 2 subtests passed.
Tested: Remote g0034 related suite test_nsa_cp_utils.py test_cp_shared_kv_layout.py test_cp_shared_kv_runtime.py: 128 passed, 5 warnings, 2 subtests passed.
Not-tested: ETE cache-hit accept-length validation after restarting prefill/decode with this synced code.
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