Transport Minister Stirling Hinchliffe on Monday reassured Boxing Day commuters there would be no unexpected service cancellations after 235 were scrapped on Christmas Day.
"Resourcing issues" prompted the changes, which were announced on Saturday evening.
The Liberal National Party opposition scoffed at Mr Hinchliffe's demands for a "warts and all" report and again called for his sacking.
"We have not seen this kind of systemic government failure since the health payroll debacle of the Bligh government," transport spokesman Andrew Powell said.
"Clearly there is a cultural rot within Queensland Rail," he said, pointing the finger at unions.
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Mr Hinchliffe ordered all services to operate for free on Christmas Day and said it was a "totally unacceptable" performance.
"In terms of crewing issues there are not expected to be any issues today," he told ABC radio.
"I want to encourage commuters to check the Translink website, but certainly the advertised timetable is the timetable that is expected to be run today."
Mr Powell predicted some passengers would instead vote with their feet.
"I think the biggest fear is that commuters have lost confidence in this rail network," he said.
QR said it "deeply apologised" to customers.
"Many people will know that we've had a lot of difficulties with resourcing the past couple of months and we are making every effort to resolve this and get more drivers on our network," it said in a statement.
QR said while many staff members worked hard to deliver services, it did not have the necessary numbers.
The Christmas Day cancellations again illustrate the fragility of the network after staff shortages caused widespread service cancellations and commuter chaos in October.
New drivers and guards are currently being trained as a government-ordered probe into the problem continues.
Earlier this month, a combination of storm damage, power outages and welding failures caused another round of cancellations and a $300,000 refund for passengers.
