qgis 2.18.28+dfsg-2 is marked for autoremoval from testing on 2019-04-09 It is affected by these RC bugs: 924833: qgis: FTBFS: sip_corepart0.cpp:38215:19: error: 'QgsPointV2 sipQgsPolygonV2::vertexAt(const QgsVertexId&) const' marked 'override', but does not override