3rd wedding band?

Okay my fiancé and I went to have my inspection done on my engagement ring and we ended up also buying my wedding bands. We don’t plan on getting married until the end of 2022 or beginning of 2023 but they told us that my bands are going to be discontinued since they are on clearance. Idk if that was a sale technique or not, but just to be on the safe side we ordered two. My actual wedding ring and then the one that will go on top to finish the set eventually. My question here is when do you usually receive your third wedding band? Like is that something you get after a couple of years of marriage? Like after setting a big mile stone? Or can you just start wearing it when you get married? I feel like I wouldn’t want to have them both I feel like we need to set a mile stone before I get to wear the third one. Idk let me know what y’all think I’m so excited to see them all together when they come in on Wednesday 🤗🤗