Originally Posted by
UKtravelbear
...Sometimes seat allocation algorithms are illogical. Once I was doing OLCI check-in and had been sat next to someone else in J yet there were empty rows elsewhere in the cabin and I was travelling on my own!
That's not entirely illogical. The computers might try to put singles next to each other to save pairs of seats for people traveling together. You can always pick a different seat at OLCI if it's available, or move in flight if there are still two unoccupied seats together at that point.