Do you mean, can different users use the New vs Classic interface but still see non-committed changes?
If so, yes - for features shared between the two plans, the modifications can be visualised in both versions. The interface is just visualisation of the data.
Just remember that some features are individual to the New or Classic interface - in these instances, the data would only appear in the interface the feature is available on.
If you are switching between interfaces yourself, it's advised you save or commit needed changes prior to doing so. If you switch interfaces and data is in an unsupported feature, these changes might not be carried over.
You do receive a warning for this prior to switching between the two versions :)
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