BAPS separated from the Vadtal diocese of the Swaminarayan Sampradaya in 1905 to 1907, a parent body distinct from BAPS itself, but no entity for that diocese or for the wider Swaminarayan Sampradaya as a parent organization currently exists in the atlas, so BAPS's branch-of relation has no live target to point at.
What would resolve this Minting a denomination entity for the Swaminarayan Sampradaya, or specifically its Vadtal diocese, with its own sourced facts, would let BAPS's branch-of relation and any other Swaminarayan-descended body's equivalent be written honestly.
OpenBAPS Swaminarayan Sanstha, History and Milestones (BAPS Swaminarayan Sanstha, baps.org)