[masarray]

Real BCUGE screenshot: 55/80 SGCB attributes, 25 unavailable during active monitoring

The current Browser switches to an isolated read-only MMS association during live reporting. NativeIec61850Client.ConnectAsync clears _liveModel, and unlike the primary discovery client the isolated reader never populates it. The structured MMS projector (TryProjectWithArIecBinding) needs the exact discovered value/type schema to resolve requested DO/DA leafs. The result is an asymmetry: direct scalar attributes such as NumOfSG / ActSG may succeed while structure-dependent reads can be blocked even when a wire response exists.

Focused fix (no speculative retry)

• Capture the current live discovery model from the monitoring device on the caller thread before isolated-reader dispatch, never from SCL-only.
• Bind this model only to the existing ARIEC structure/scalar projection path in the independently connected NativeIec61850Client; no second network discovery, report subscription or control write.
• Fail closed when model object, projection epoch, association, IP/port, or live/monitor lifecycle changes. Validate at binding and for each read.
• Keep the existing sequential bounded read and 5s per-target timeout; preserve report ingress as canonical authority.
• Regression tests cover successful live lease, refusal for SCL-only/offline, model/endpoint/association invalidation and rejection of disconnected-client schema injection.

Expected measurable outcome: more model-bound structured SG/DA leaves may decode during live monitoring, but this is not yet proof that all 25 BCUGE failures are resolved. Field evidence and per-attribute error diagnostics still required.

Stacked on #596. Keep draft; no main merge, pinned engine update, protocol write, automatic polling or release.

[masarray]

D6 semantic reconciliation — verified live schema lease preserved, close historical carrier unmerged

Disposition A — safe historical supersession, not a source merge: original head 326525c90cec384190abf21eda43510153dfc17d is an exact ancestor of integrated draft RC 817c3910e8223fa2ac531a4426ada5d2d4bbbe50 (+1275/-0; merge base old head). Four of four touched paths verified individually; original branch/head kept recoverable.

Canonical replacement: protected RC #727 / #729 at 817c3910e8223fa2ac531a4426ada5d2d4bbbe50.

Unique delta / source proof: Models/IedBrowserIsolatedReadSchemaLease.cs old and RC exact blob 8ffa03bf40ba7f29db9ebbdc04aeea2c8082dd2b, captures only connected/monitoring verified live model with association, Browser projection epoch, IP+port, exact model reference and offline fence; refuses SCL-only promotion. tests/ARSAS.Tests/M214IsolatedBrowserSchemaLeaseTests.cs old/RC identical blob 26842618182ef5372eef6eea14eb21f981242d09, all 4 original tests retained.

Services/IedBrowserIsolatedReadService.cs old 3b1521c8abcc5ca1d0b6f55f2996964c9ecc9ef1→RC 9d0ad89e99ba1953c354faace8c6f13b529b712b: unchanged capture before thread crossing, lease.IsCurrent(device) before model binding and repeatedly before individual Read, client.BindIsolatedBrowserReadSchema(lease.Model); subsequent RC adds model-bound typed-DO root handling and TryAcceptVerifiedMmsString, a strictly wire-type-verified fallback rather than obsolete arbitrary structure coercion. Services/NativeIec61850Client.cs old 0cff7ebaa10764e025f9b488bae1356e7922f112→RC b74398faf4d206286ab1dcac8b6e5ab414783393: exact connected fresh secondary client only guard !IsConnected || _liveModel is not null || _lastDiscovery is not null still rejects unsafe injection; same _liveModel = verifiedLiveModel schema-only binding. No RCB, Write, subscriber, native command, or duplicate value cache introduced by this historical branch.

Safety: In this closure no code, engine lock, protected RC, published v1.6.42 or main changes. The exact #753 six-file head 410a2fd3c8757f9c9cac46e2df6cb4ce047585b7 now has Windows/native/package + SCL CI successful (Windows, SCL); this does NOT prove live secondary association with a physical IED.

Follow-up: Retain live association/model lease tests and physical multi-client capacity/error tests on the active RC. #615 Control late-flight alias, #606 GOOSE/SGCB parity and #729 physical signoff remain separate. Do not read closure as IED FAT acceptance.