Possible issue on specific Column Type

I am working on a component that searches for drifts on measurements taken over time. The detected drifts in the data are stored as List (Collection of Zone Date Time) (Column Type) in an output table. However, when there is more than one drift in a single measurement, they are not recorded:

I suspect the bug is related to an aggregation on timestamp run in the preceding GroupBy node:

To overcome this issue, I removed the zones from the timestamp column in the input data, and then it works with no errors (i. e., the multiple drifts are always displayed).

and the Column Type now is List (Collection of: Local Date Time).

Another complicating issue is that the error is not consistent, i. e., it occurs in a somehow random manner. When it occurs, it is normally related to me testing the component with distinct input data and interchanging them at every execution.
Error happened in both KNIME AP and in KNIME servers.

I wanted to know if zoned timestamps has caused similar issues to other users. Thank you!

Welcome to the KNIME Forum! When you say the error is not consistent, do you mean it fails on a table and then when you rerun the GroupBy, it works? Or is it consistent for a dataset, but on another dataset it fails? If it is the latter, could you share a dummy dataset that does not work?
Kind regards,

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