The new operator has taken over the West Coast Main Line for the first time today, but it's not been without teething problems.
Avanti West Coast took over the franchise on the line, which was previously run by Virgin for 22 years, on Sunday.
Its parent company is a partnership between Scotland-based First Group and the UK arm of Italy's main train operator, Trenitalia.
But just a few hours in and passengers have have already inundated the company's Twitter feed with questions - because its website wasn't working properly.
The message: "We're sorry, we can't take you to our website right now' appears on the home page.
Passengers can still book tickets , download the app and contact the operator via a 'holding page', while it is being fixed.
Contacting the company on social media, Stevie Roberts wrote: "Good start. Your website doesn’t work".
While Andrew Fernandez wrote: "Trying to book tickets Lancaster-London Euston for Jan but cant access website. Not a good start not impressed worried about reliability if you cant even have a website."
Meanwhile Simon Mouncher Tweeted: "Great start. No catering on the 12:37 to Manchester Piccadilly. Forgot to pick up the catering staff!"
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Other passengers expressed annoyance that the seat selector function has disappeared.
BigGbythesea Tweeted: "You won't be seeing me until you resurrect the seat selector for booking tickets!
"Why have you removed this facility? This is useless".
Replying to another passenger, Avanti confirmed that the function has gone, and there are no plans to reinstate it at present.
A spokesman for Avanti West Coast said: "We expect the new website to be up and running shortly once a few teething problems have been sorted".
So far, there don't appear to be any major issues with the actual train service however.
National Rail is currently reporting that a 'good' service is operating on the line, with no major delays.
The final Virgin train left Piccadilly last night.
The first train featuring Avanti West Coast livery to arrive in Manchester will be Monday's 8am service from Euston, which is due into Manchester Piccadilly at 10.08am.
