West Coast Main Line: Avanti ordered to release tickets earlier
Avanti West Coast (AWC) has been ordered to stop releasing rail tickets only a few days ahead of travel.
Passengers claim it means they are often being denied cheaper tickets.
Rail regulator the Office of Rail and Road (ORR) said AWC must submit an improved recovery plan by 2 February for producing timetables and releasing tickets or face "formal measures".
The company has apologised, citing industrial action and engineering works.
AWC runs services on the West Coast Main Line between London Euston and Glasgow Central. The route also serves the Midlands, North West of England and North Wales.
Passengers wanting to book tickets for weekend travel this month have only been able to purchase tickets a few days in advance.
Weekday tickets have also been released far later than the 12-week booking window normally used by rail operators.
AWC said the delay had been caused by having to produce bespoke timetables - in partnership with Network Rail - during engineering work.
Tickets can only be made available for sale once timetables are confirmed.
'Inconvenience'
AWC initially made "reasonable progress" against an improvement plan created in September, with passengers given more notice to book travel in the run-up to Christmas.
But, according to the ORR, the "position has deteriorated" this month.
Current plans for February show a "better picture for weekday travel, but still fall short of passengers' needs for weekend journeys", the regulator added.
ORR strategy, policy and reform director Stephanie Tobyn said passengers were "rightly frustrated that this situation has deteriorated so quickly after a steady start to the recovery plan late last year".
She added: "By 2 February we expect Avanti to identify what has gone wrong and set out how it intends to get back to releasing timetables in normal industry timescales so that passengers can plan and book journeys with greater confidence.
"Failure to produce an acceptable plan or to deliver improvements may lead to more formal measures."
An AWC spokesman said: "Unfortunately, some tickets for Saturdays and Sundays have only been available at short notice due to having to write unprecedented numbers of bespoke timetables to accommodate industrial action and engineering work which has stretched industry train planning resources.
"We know this causes huge uncertainty and inconvenience for passengers, and we're sorry for that.
"Weekend tickets are now on sale up to mid-February, and by mid-March we'll be selling weekend tickets six weeks out."
It emerged on Monday that the operator cancelled the equivalent of about one-in-five services during the four weeks to 7 January.
The company said "performance has steadily improved" since then.
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