Developed enhanced time series export functionality for the powsybl-core repository, enabling support for non-contiguous version exports to improve data handling flexibility. Leveraged Java for backend development, extending the data model and export logic to accept lists of versions rather than requiring contiguous sequences. Focused on robust implementation by introducing comprehensive unit tests, particularly for CSV exports, to validate correct behavior and prevent regressions. This work addressed the requirements outlined in GitHub issue #3780, ensuring backward compatibility while expanding export capabilities. The approach emphasized maintainability and reliability, strengthening test coverage and supporting more versatile analytics for end users.