Rail services returned to normal today on London Midland lines following the cancellation of all but one of the firm's trains yesterday because of staff shortages.
Thousands of rail passengers suffered delays and disruptions to their journeys after the company cancelled all its trains except those on the Birmingham to Liverpool line.
London Midland, which operates more than 1,200 services a day to 149 stations, was criticised after revealing its drivers usually worked on a voluntary basis on Sundays and not enough staff volunteered to work yesterday.
Talks will be held this week between the company and union leaders in a bid to avert a repeat of the chaos.
The company said an agreement to increase overtime pay on Sundays from time and two thirds to double pay ended on August 30.
National Union of Rail, Maritime and Transport Workers (RMT) leader Bob Crow said it was simply a case of staff exercising their contractual right not to work on Sunday.
"This is a voluntary arrangement. Rather than pleading ignorance and blaming their staff, the company should focus their energy on resolving the issue," he told the Press Association today.
A London Midland spokeswoman said: "We have scheduled meetings with the unions this week and we will be contacting them today to discuss the fact that in their comments to the media they raised the issue of overtime payments as a reason for staff not volunteering.
"They have not previously advised the company they wanted to discuss the continuation of the short term, double-time agreements."
The Birmingham-based company runs train services throughout the heart of England, serving major cities including London, Birmingham and Liverpool, and linking scores of towns across the midlands.
Conservative MP Mark Pritchard has asked Transport Secretary Lord Adonis to investigate the disruptions.
Speaking for the Northampton Rail Users' Group, one of the largest towns served by the network, Shaun Hope said: "It's a shambles. How can they run an essential service on a voluntary basis? It's an astonishing way to operate a train service."
London Midland made arrangements for other companies to honour their tickets and also put on some bus services yesterday.
Operations and Safety director Andy Thomas apologised for the disruption.
He said: "Where we have had staff coming to work we have run services and also ensured we prepare the trains and operations behind the scenes to start Monday morning services overnight."
He added the double pay deal for Sunday working was on top of existing overtime and was "time limited".
He said: "These extra payments were always temporary and it was clear they came to an end on August 30. This week London Midland drivers and conductors would have earned the usual, agreed level of overtime for working a Sunday shift."
Shadow transport secretary Theresa Villiers said: "London Midland needs to get their act together. They really should have contingency plans for a situation when their regular drivers don't put their names down for Sunday shifts."