Time Warner Cable Inc., which is planning to combine with Comcast Corp., said Internet service is largely restored after frustrated subscribers across the U.S. reported outages this morning. An issue with its Internet backbone disrupted broadband and on demand services at 4:30 a.m. New York time during “routine network maintenance,” the New York-based company. As of 6 a.m., “services were largely restored as updates continue to bring all customers back online.” Subscribers woke up to no Internet access, and #timewarnercable quickly began trending on Twitter as customers vented their frustrations. The nationwide outage struck in the midst of Comcast’s efforts to gain regulatory approval to acquire Time Warner Cable for $45.2 billion. Since the deal was announced in February, the companies have faced complaints about poor customer service as they try to win support from both regulators and the general public.