I'm learning about the mempool and found this text on a bitcoin educational site: Once the Mempool reaches full capacity, nodes start prioritizing transactions by setting up a minimal transaction fee threshold. Transactions with a fee-rate lower than the threshold are immediately removed from the Mempool.

If a transaction is removed from the mempool, where does it go? To some holding area, I assume, for possible inclusion in the next block? What is the name of the holding area and where does it reside? Thx.