I had sort of the opposite situation. I had made hut reservations far in advance. We signed out with the rangers at Badger Pass, and we were on the ski trail by 9 a.m. We got to the hut around 3 p.m., and to our amazement, the place was locked up tighter than a drum. We had no idea what had gone wrong. However, we were starting to size up the situation for a forced bivouac on the stone front porch of the place. We figured that if we huddled our sleeping bags close enough, we would make it through a cold night without many serious problems. Then I looked into breaking into the hut. All of the doors were locked, but the windows had metal gratings over them. Out of my backpack I produced some small vise-grip pliers, and I used those to back out the lag screws that fastened the gratings to the stone walls. After about 30 minutes, we had screws out and one grating lifted away. The glass and metal windows were chained from the inside, so I carefully used one padded elbow to break out one glass pane. Then I unchained the window and opened it on the inside. Each of us had to crawl under the grating, then over part of the window to drop into the hut interior, and it was cold and dark. We lit one candle, then lit the wood stove, and we were headed toward a decent situation.
Right then, the hutmaster showed up, unlocked the front door, and told us that we were all under arrest (joking). He saw that we did what we had to do, so he understood. He had intended to be there early in the day, but a sudden family emergency had called him away. He zoomed in to catch us before we got into too much trouble. The next day, we spent time to help him repair the window and replace the grating.
–B.G.–