Another idea

[ozbob]

Trains out of Caboolture - Ipswich every 20 minutes.

Petrie to Richlands every 20 minutes.

So Petrie <-->  Darra trains every 10 minutes.   Caboolture -  Petrie 20 minute, Ipswich  - Darra 20 minute.

Peak add to this expresses etc.

[somebody]

I don't think it's a bad idea, but it is a less good idea than the 8tph solution which allows a tiered service.

EDIT: to elaborate, does the increased frequency for Auchenflower/Taringa/Chelmer-Oxley outweigh the benefit to the stations beyond Darra from having a tiered service?  Personally, I think not.

[Cam]

EDIT: to elaborate, does the increased frequency for Auchenflower/Taringa/Chelmer-Oxley outweigh the benefit to the stations beyond Darra from having a tiered service?  Personally, I think not.

I agree. The sooner the Ipswich to Caboolture line becomes a tiered service, the better. The travel times to/from the outer suburbs are too lengthy & the draft 2011 timetable has them becoming several minutes longer.