Yes the solution is to let stations already deployed to update themselves on a delay configured via GPO, new stations get the current release based on a deployment image you can make with ye old CTRL+SHIFT+F3 method, yes that means you have to make a new deployment image for all those Dells and push it to each station... and sometimes you have to use a keyviewer to pull the key from the BIOS and manually stuff it in to get the machine to activate, but that process is still quicker than 30min per station to preinstall the most recent release.
The other option is to deploy with whatever the thing has and let the unit upgrade itself, which while annoying isn't wrong either. It's not like users aren't going to have to deal with this little semiannual chore going forward.
Most shops I know are simply doing what MikeRoq suggests, blowing away what the OEM shipped and replacing it with a fresh MS stock install and going from there. Nuke the bloat, and solve the update issue all at once.
Oh, and if you havne't already, no new machines without SSDs... if you think 30-45min is bad, try installing that update on a platter disk and sitting there for 1.5-2 HOURS.