You are no longer on the same downstream frequency.
When you first posted, you were on 331 MHz, now that the modem has locked on, it's on 323MHz.
Your downstream power level is way too low and when i say you are scraping the bottom of the barrel with that level, i'm not joking. It might stay online for a while but i would expect it to drop offline at some point, make sure you have some credit on the dongle for tomorrow just incase.
As for why it's come online now, the signal levels on the network do fluctuate up and down. As the temperature drops, the signal levels do go up slightly
Also with less people online there is a chance that there is a lower amount of noise on the network, allowing you to connect again for a while.
HTH