Another twist has emerged in the Optus outage saga after the telco’s Singapore-based parent company bought in yesterday to say a botched software upgrade wasn’t the cause of the meltdown. That’s a bit awks because it contradicts what Optus and a company insider claimed earlier in the week… Singtel said Optus was aware it was running a “routine upgrade” on its international internet exchange and that the Aussie network remained “up and running” after the upgrade was completed. It adds to the many questions CEO Kelly Bayer Rosmarin will face when she gets a grilling by a Greens-led Senate Committee this morning, where the focus will be on what steps Optus is taking to avoid another national outage and the compensation it offered to affected customers. It’s no wonder the Financial Review reports this morning that she’s considering resigning (paywall)….