According to a Medium post

Terra 2.0 Reveals LUNA Airdrop and Launch Date

Terra Luna 2.0 Airdrop – Answers to Most Common Questions

According to a Medium post, eligible holders of LUNC (Luna Classic), USTC (UST Classic), and aUST – will receive the LUNA airdrop on the new chain upon genesis.

LUNA 2.0 listing and Terra airdrop distribution schedule

Terra Chain 2.0 and LUNA Airdrop Approved for May

All You Need To Know About Terra 2.0 and the LUNA

Terra 2.0LUNA Airdrop - Medium