How long before I order a custom unit?

I’m new to chastity and currently wearing a CB6000S. While cleaning it today, I realized that when my official release comes this Sunday, I might need to switch to a smaller ring. After reading through some discussions, it looks like others have managed to reduce their size over time?

My main reason for asking is that I’m planning to order a custom device soon. Since my wife (KH) and I are celebrating our 20th wedding anniversary in Vegas this July, I’d like to present her with the new gear as a token of my devotion. However, I haven’t checked yet what the production lead time is for one, so I don’t want to order too early only to discover later that I still need to downsize. My testicles have always sat high and tight, but between being full of semen and using plenty of lotion (as advised here), they seem to be stretching out.

Will my size continue to decrease? If it does, is this something that happens over weeks or months?

I’d appreciate any advice from more experienced members. Thanks.