Gap in the data

First of all, amazing data set!

There seem to be a gap in the data or a little bug in the notebook example_building_footprints.ipynb. These arethe buildings extracted with AOI

           [
            [
              -0.31158648247856036,
              51.67080399034276
            ],
            [
              -0.31158648247856036,
              51.55175362366529
            ],
            [
              -0.12320075078847026,
              51.55175362366529
            ],
            [
              -0.12320075078847026,
              51.67080399034276
            ],
            [
              -0.31158648247856036,
              51.67080399034276
            ]
          ]

and tiles
[31313113, 31313131]

As you can see there a strip missing.

I have downloaded the geoJSON containing all the areas covered and there should be data at these coordinates.

Any advice/suggestion?

Start with example_building_footprints.ipynb and reproduce the reported AOI using tiles 31313113 and 31313131. Compare the extracted buildings with the coverage GeoJSON at the supplied coordinates to determine whether the strip is caused by the notebook or missing source data. Done means the cause is identified and the issue has a documented, reproducible result.