FL2VA CONTINUOUS AV · Phase-Aligned Latent Handover

Two node IDs in this pack point at exactly the same class, and this is one of them. IAMCCS_MiniMaxH3HerrgottsDirectAVChain is the older identifier for the continuous AV chain; IAMCCS_MiniMaxH3FL2VAContinuousAV is the current one. Both display the same name in the add-node menu, both take model, clip, video_vae, audio_vae and cine_linx, both return frames, audio, bridge_last_frame, sampled_latent, fps and report.

The registration looks like this:

NODE_CLASS_MAPPINGS = {
    "IAMCCS_MiniMaxH3ContinuousAVSegment": IAMCCS_MiniMaxH3ContinuousAVSegment,
    "IAMCCS_MiniMaxH3FL2VAContinuousAV": IAMCCS_MiniMaxH3FL2VAContinuousAV,
    "IAMCCS_MiniMaxH3HerrgottsSegment": IAMCCS_MiniMaxH3ContinuousAVSegment,
    "IAMCCS_MiniMaxH3HerrgottsDirectAVChain": IAMCCS_MiniMaxH3FL2VAContinuousAV,
}

Two names, one object. Not a subclass, not a shim with its own logic - the same class object registered twice. Which means it is literally impossible for the two IDs to behave differently.

Why a pack does this

Workflows serialize node types as strings. Rename a class and every graph built on the old name comes back as a red missing-node box, and the user has to hand-edit JSON. Keeping the retired identifier registered costs one line and saves everyone that afternoon. Any time you see a (Legacy ID) suffix in a display name in this pack, that's what is happening.

What to do with it

Existing graph on the old ID: do nothing. It queues, it renders, it produces the same result as the new ID.

New work: use IAMCCS_MiniMaxH3FL2VAContinuousAV. Because H3 Settings' task mode drives which continuity backend is expected, and the newer nodes and the lazy router all refer to the current IDs, staying on the new name keeps you inside the supported path when the pack version moves.

What you should not do is put both in one graph. They're distinct node instances even though they share a class, and each triggers its own render of the whole authored programme - two full chains, two deliveries, and a slow way to find out they were the same node.

For the mechanism - phase-aligned latent handover, the 5/22/39-frame context window, why authored keyframes win over the provider's automatic handover, and why the video crossfade defaults to zero - read the canonical page:

• FL2VA Continuous AV · Phase-Aligned Latent Handover

Install

The pack install is the only install:

cd ComfyUI/custom_nodes
git clone https://github.com/IAMCCS/IAMCCS-nodes.git

Or Manager → search IAMCCS, restart. Nothing extra for this node itself. If a graph using it reports a missing node, the cause is almost always the pack being absent, half-installed, or present twice in custom_nodes - not the alias.