I thought (and you probably thought) that the hack interfered with the pumps delivering fuel through the pipeline.
Nope. Nope. Nope.
The pipeline was fine. The flow of gas was not impaired. What was hacked was the company's billing system, as explained at Jalopnik:
The cyber attack that shutdown the Colonial pipeline causing a gas panic and stoking fears of gasoline shortages, didn’t actually shut down the pipeline. It impacted the billing system at the Colonial Pipeline Co., which shut it down because they were worried about how they’d collect payments.Yes, the fuel-carrying pipeline was shut down last week in order to prevent a company that is entrusted with what should be a public utility from enduring an accounting headache...The company halted operations because its billing system was compromised, three people briefed on the matter told CNN, and they were concerned they wouldn’t be able to figure out how much to bill customers for fuel they received.
More at the link.