Hello, let me explain in detail.

We use a decentralized platform to exchange bitcoin into monero. Then the monero is sent to a wallet generated not depending on any centralized platform after that the Monero is exchanged back to bitcoin via this same platform. The fact of using a monero intermediary wallet that doesn't depend on any service ensures greater anonymity and, what's more, monero uses the stealth address principle. Here's a detailed explanation of stealth addresses: https://www.getmonero.org/resources/moneropedia/stealthaddress.html

We currently have no XMR or BTC pool for the advanced method. Over time, we'll probably integrate a Monero and Bitcoin pool. This means that only one exchange will be made from Monero to Bitcoin. The advantage is that when the user sends funds in BTC, the equivalent amount in Monero will be exchanged directly into Bitcoin. Anonymity would be further strengthened.