Rule: Moving a sent message to specific folder!

I am using (glorious/full featured) Fastmail as my webmail. One of the exceptional features of Fastmail is that it keeps a copy of all your sent messages no matter it’s checked in Desktop/Android/iOS email client or not!
Here is my story with em Client:
1- I unchecked " save a copy of sent messages " in em client settings to prevent double messages in my sent folder.
2- I created a rule to move specific sent messages to specific folders other than “sent”.
Now, when I send a message, it’s saved in “sent” folder by my webmail AND a copy of it is saved in specific folder.

Q: when I choose " Move to folder " in em Client rules, why doesn’t it move but copy it? That is, if it’s the concept of “moving”, it should check “sent” folder and moves the message to my specified folder.

Ps. I m using Imap account!

em Client is WONDERFUL and I love it beside with TheBat!

unfortunately, moving a sent message to a folder when using Fastmail, Google and few others, is not currently possible.

It’s a regret!