Scotia was the name given to the offshore portion of BIH when it was bought by CHC. The onshore (or Penzance and some Falklands work) was retained by BIH.
CHC Helikopter Service is a separate company although they share resources. CHC Helikopter Service was formed in 1999-2000 when CHC purchased the majority of Helikopter Service shares.
At that time, Helikopter Service owned 49% of the old Bond Helicopters but had an agreement to purchase the other 51%. When that sale was completed, CHC ended up owning The assets of the old BIH, Bond Helicopters and Helikopter Service.
Scotia is therefore an amalgam of BIH, and the old Bond Helicopters with CHC Helikopter service as a separate but obviously related company.