That's almost certainly your laptop manufacturer's fault. Dell pushes BIOS updates via Windows Update on a regular basis, and I've never had the settings reset because of said update. (source: I administer 80 Dell desktops, 40 Dell laptops, and 8 Dell servers)
However, I do feel your pain, I don't understand why other motherboard manufacturers don't save your existing BIOS settings. Asus and MSI, I'm looking at you all... why can't you just ask me instead of undoing my work?