Fine-tuned on DialectSentEval 2026 Subtask 2 (Arabic Dialect Sentiment Swap): given an Arabic sentence and its polarity, rewrite it to express the opposite polarity while preserving meaning. One of 6 trained backbones behind NAMAA Community's submission (formerly S03_arat5_msa_msa_prefix_tag in internal experiment logs).

This checkpoint alone is not our best system — reranked sampling and cross-backbone ensembling on top of these checkpoints reach 96.78 development accuracy and 0.7597 on the official hidden test set. See the repository for the full pipeline, results, and the honest dev/test generalization-gap analysis.