That's only if you don't have a lot of time out. If you're planning to be out for a while I'd avoid being too exposed during the 12-3 window.

I agree, but you can titrate your exposure. So at the beginning of the season, in the 12-3 window you can start by going 5 mins without sunscreen for a few days, then 10 mins, then 20 etc. depending on your skin type.

The worst thing to do is to go from low exposure (i.e. winter months, or just constant indoor time) to long periods of exposure, even with sunscreen.