Backdating Permalinks

Hello,

I am working on a travel blog / dairy. I preferred the permalink format I am looking at is:

domain.com/travel/”country”/%year%/%monthnum%/%day%/%postname%

It is kinda long, but I think that it’s pretty sensible for the purpose of my blog.

Since I have contents that pre-date today (and indeed, the day I started my blog), I would need to backdate some posts. No problem there.

However, I found that %year%, %monthnum% and %day% is based on the current day, and unlike %postname%, can’t be edited.

Is there a known workaround, perhaps via a plug-in?

Thanks!