Whatever they r called. Most, if not all islands in the W. Pacific have different names since the time immemorial.
The CV-16 & CV-17 could've practiced invading other islands closer to their bases, so sending both to the SC Sea now, with current PRC-US tensions, looks like the real thing to me. To contain Taiwan & force it to renounce independence, it must be truncated at sea & in the air. Also, taking Taiwanese held islands would outflank other claimants + help monitor & control the SC Sea.