You can the detailed info about the Coreum airdrop here https://sologenic.medium.com/guidelines-for-solo-holders-to-establish-a-trustline-to-receive-coreum-core-airdrop-9a705336f4c6

You can only received an airdrop if you have $SOLO tokens stored on XRP Ledger or any decentralized wallets that support $SOLO tokens which already mention on the article that I share here. The snapshot of your balance is done at random time so make sure to convert your BSC tokens to XRP tokens since it’s the only way to snapshot your rewards. The easy way is to deposit your tokens on CEX that supports the snapshot of this airdrop for a less hassle transition for you.