Just did 4 Bountiful Delves. 1x Tier 11 with treasure map. then 3x Tier 8 one with glowing muskrat fella. Great Vault showing 4 complete. Weekly Quest - A Call to Delves showing 3/5 only.
Edit- Just checked and vault is not tracking the tier of the delves properly either. Showing one of the delves as a tier 7 which was not the case.