I think its fair to say it looks like Commsec are being...

I think its fair to say it looks like Commsec are being conservative, however TPG does have quite a few things to address which can potentially slow earnings.
The margins on NBN are lower than Telstra Wholesale, so as the NBN Rollout continues it will impact on margin. TPG is rolling out its 4G Networks in Australia and Singapore.. There will be considerable Capex, marketing costs, operational costs getting these networks running. The interest bill for their Spectrum purchases is also ticking away.. They will also need to spend a considerable amount of money on 5G Spectrum if they want to remain relevant. In addition as they have acquired companies they are yet to merge accounting/billing/provisioning/IT Systems. This will be crucial in years to come to remain a highly profitable low cost telco.. Which they have done to date so well.. Its now becoming fairly obvious that mobile plans will become unlimited in Australia in the near future. This will need 5G and a lot of spectrum for 4G as well..