What do confirmations mean?

Pending status, block inclusion and depth in the chain.

A transfer is pending

The operation is not included in a block yet. A hash helps you locate it but does not itself confirm receipt. Check the network and status in that blockchain’s Explorer.

A transfer is included in a block

The transaction page shows a block number and confirmation count. New blocks increase the record’s depth in the current chain. The Explorer links the transaction to its block so you can inspect both.

Can the status change?

Yes. A chain reorganization can remove a previously accepted block, changing the transaction’s confirmations. A confirmation count is not unconditional finality; the additional QNV finality model under research is not claimed to be active.