Difference in support between buying a phone with preinstalled e/os vs installing it myself

I would like to buy a Fairphone 6 and run e/os in it. Online of course they sell phones with me/os preinstalled, but at a local retailer I can get only the version with regular android.

I would prefer to buy from a local shop rather than buying online, so my question is, do they support e/os self installs the same as preinstalled e/os?

Thanks in advance!