You will not be able to do so since it is a power up (signified by arrow in the circle icon for the Daily document)
This you should be able to do. However, you do not have a day generated by default every day unlike some other apps. So have you made an April 5th document already before doing this? You can do this by pressing Alt + D or going to the sidebar & hovering over your documents & select the Today’s Document option. After that when you try moving it you should be able to find the date.
Depending what exactly you are trying to do you could go to the date you are interested in & create a portal or a reference instead. Or when you are at the rem in question you could do the same thing or press !! & select the date depending how you are wanting to connect things up
Hope something here is of help to you