I think the timeline all depends on the processing officer and if there are no issues with your documentation. My timeline is below in case you may find it useful.
ITA: 21/09/17
Application submitted: 5/10/17
AOR: 6/10/17
PPR: 1/11/17
GCKey Approval: 16/11/17
PUM: 23/11/17
Instructed DHL to pick...