Every fact in this record, and where it came from. Editorial derivations say so.
regionmedium
wh40k.lexicanum.com/wiki/Interceptor_City_(Novel ) §Cover Description — 'a gruelling war of attrition for the fate of Vesperus during the Sabbat Worlds Crusade — a dead hive on the planet Lysander nicknamed Interceptor City'. The description names Vesperus as the war and Lysander as the planet under the hive; this record carries Vesperus, the name the campaign is fought under, and notes the second name here rather than guessing which is the world
region-basishigh
wh40k.lexicanum.com/wiki/Sabbat_Worlds 'a group of star systems along the edge of the Segmentum Pacificus'. This dataset already carries that cluster (Tanith, Phantine, Urdesh, Herodor, Balhaut and the rest); this world is placed inside it
gposlow
inferred: cluster-level. Placed inside the existing Sabbat Worlds cluster on the Pacificus edge. Which system within the cluster is not published