You certainly can make one. I don't know why homebrewers think Oktoberfests have to be brewed in March. German breweries don't even do this anymore. Lagering times follow brewing science not ice-cave lagering traditions:cross:. I would keep it on the lower end of OG, though, so your reduced lagering times won't be a big deal. Noonan recommends lagering 7-10 days (for a dextrinous wort, which an Oktoberfest typically is) for each 2 degrees Plato (8 points of OG). So, if your OG was 1.050, you could lager for 6 weeks and be OK.