After you upgrade you CAN do a clean install, but NO they aren't likely going to make one.Dont hope too much for a Surface Pro 3 recovery Windows 10 disk/ISO. The recovery disk requires a key to activate, and the key on bios for the SP3 is for Win8 and not 10. MS is giving a free upgrade, but not a full license to perform a clean install.
After you upgrade you CAN do a clean install, but NO they aren't likely going to make one.
From Microsoft's Documentation on Clean Install:You mean a full "refresh" with or without keeping data.. You can't clean install windows 10 without a purchased key.