Suno retired every pre-v6 model while keeping songs made with those models unchanged in users’ libraries. You can still listen to them, share them, remaster them, and use them for Covers. What disappeared is the engine that originally made them.
Old tracks therefore have two very different kinds of continuity. The audio file survives, but the generation environment does not. If a v5.5 prompt produced a particular vocal grain or arrangement habit you liked, there is no longer a v5.5 button for creating another take under the same conditions.
The licensed Suno v6 transition moves new creation onto the v6 family even when the starting material came from an older model. Existing work has not been deleted or silently converted. New branches of it, however, belong to a different model generation.
Any fresh iteration uses the current v6 models. An old verse can survive untouched while a newly generated chorus comes from a different system with different training, behavior, and controls. For unfinished projects, this means “continue the song” no longer means “continue using the model that made the song.”
A prompt archive still helps, but it is not a time machine. Saving lyrics, style tags, timestamps, and generation settings can preserve your intent, yet those records cannot restore a model Suno has removed. Reusing the same words in v6 may produce a useful relative of the old track without reproducing its exact character.
The wider problem is familiar in generative music work. Research on reproducible music generation treats implementation choices and model configuration as part of what makes results repeatable. Once a production system changes, keeping the input text alone does not preserve the original conditions.
Creators with a recognizable Custom Model workflow should expect continuity of identity, not identical behavior. The catalog used to personalize the model may still represent your sound, while the underlying generator has changed underneath it. A favorite prompt and the same Custom Model name can therefore lead to a different balance of vocals, structure, texture, or prompt obedience.
Old Custom Model songs are not rewritten during this upgrade. Suno specifically separates the stored song from the model used to make future material. This matters when comparing an older release with a fresh generation, because differences do not automatically mean your original track or training catalog was altered.
The safest comparison is practical rather than nostalgic. Put an old Custom Model song beside a new v6 generation made from a familiar brief and listen for the parts your workflow depended on. Vocal consistency, section length, instrumental density, and the way style tags are interpreted matter more than whether the new version is broadly described as higher quality.
This changes how you should think about versions inside one project. The original render is now fixed source material, almost like an imported recording, while any generated replacement or continuation comes from the current system. If one old take contains a vocal performance you cannot afford to lose, preserve that take instead of assuming another generation can recover it later.
Remastering deserves the same caution. Suno still allows old songs to be remastered, but a remaster is a new operation rather than proof that the old model remains available behind the scenes. Compare the result with the original before treating it as a replacement, especially when the older model’s quirks were part of what made the song work.
Model retirement also breaks a common habit of going back months later and asking an older engine for sibling versions. You can still branch from the audio you kept, but you cannot reopen v4.5 or v5.5 as a historical production environment. The library remembers the song. It does not preserve the machine that sang it.
Old tracks therefore have two very different kinds of continuity. The audio file survives, but the generation environment does not. If a v5.5 prompt produced a particular vocal grain or arrangement habit you liked, there is no longer a v5.5 button for creating another take under the same conditions.
The licensed Suno v6 transition moves new creation onto the v6 family even when the starting material came from an older model. Existing work has not been deleted or silently converted. New branches of it, however, belong to a different model generation.
Old songs stay intact while new iterations change
Suno says an existing song remains exactly as it was after its model is retired. Playback and sharing still work, and old material can remain the starting point for an extension, remix, remaster, or Cover. The important catch arrives as soon as you ask Suno to create new audio from it.Any fresh iteration uses the current v6 models. An old verse can survive untouched while a newly generated chorus comes from a different system with different training, behavior, and controls. For unfinished projects, this means “continue the song” no longer means “continue using the model that made the song.”
A prompt archive still helps, but it is not a time machine. Saving lyrics, style tags, timestamps, and generation settings can preserve your intent, yet those records cannot restore a model Suno has removed. Reusing the same words in v6 may produce a useful relative of the old track without reproducing its exact character.
The wider problem is familiar in generative music work. Research on reproducible music generation treats implementation choices and model configuration as part of what makes results repeatable. Once a production system changes, keeping the input text alone does not preserve the original conditions.
Custom Models move forward even when their songs do not
Custom Models create a sharper version of the same split. Suno says previously created Custom Models are automatically upgraded so v6 powers them going forward. Songs made with an old v5.5 Custom Model stay available and playable, but the personalized model used for future generations is no longer running on v5.5.Creators with a recognizable Custom Model workflow should expect continuity of identity, not identical behavior. The catalog used to personalize the model may still represent your sound, while the underlying generator has changed underneath it. A favorite prompt and the same Custom Model name can therefore lead to a different balance of vocals, structure, texture, or prompt obedience.
Old Custom Model songs are not rewritten during this upgrade. Suno specifically separates the stored song from the model used to make future material. This matters when comparing an older release with a fresh generation, because differences do not automatically mean your original track or training catalog was altered.
The safest comparison is practical rather than nostalgic. Put an old Custom Model song beside a new v6 generation made from a familiar brief and listen for the parts your workflow depended on. Vocal consistency, section length, instrumental density, and the way style tags are interpreted matter more than whether the new version is broadly described as higher quality.
Finishing an old project now means accepting a model boundary
A half-finished pre-v6 song can still be worked on, but every generated addition crosses the boundary into v6. Extend can continue the piece, Cover can reinterpret it, and other editing tools can use the existing audio as source material. None of those operations restores the retired model.This changes how you should think about versions inside one project. The original render is now fixed source material, almost like an imported recording, while any generated replacement or continuation comes from the current system. If one old take contains a vocal performance you cannot afford to lose, preserve that take instead of assuming another generation can recover it later.
Remastering deserves the same caution. Suno still allows old songs to be remastered, but a remaster is a new operation rather than proof that the old model remains available behind the scenes. Compare the result with the original before treating it as a replacement, especially when the older model’s quirks were part of what made the song work.
Model retirement also breaks a common habit of going back months later and asking an older engine for sibling versions. You can still branch from the audio you kept, but you cannot reopen v4.5 or v5.5 as a historical production environment. The library remembers the song. It does not preserve the machine that sang it.
