More than two months have now passed since former shadow childcare minister Tulip Siddiq stood down from the front bench on 26 January, but Labour is yet to appoint a replacement, with the post currently vacant.
This is despite the sector currently preparing for major change, with free childcare provision set to be extended from 15 hours a week to 30 hours a week in just five months' time.
Pre-school Learning Alliance chief executive Neil Leitch said the introduction of the 30-hours offer, and an associated shake-up to the way providers are funded, require "effective scrutiny".
"We're disappointed that, two months after Tulip Siddiq's resignation, Labour has yet to appoint a new shadow early years minister," Leitch said.
"The sector is at breaking point - every week we're hearing reports of providers closing down as a result of underfunding.
"And while we know that Labour has been raising concerns over childcare funding over recent weeks and months, a permanent shadow minister will undoubtedly play a critical role in holding the government to account."
His concerns have been echoed by London Early Years Foundation chief executive June O'Sullivan.
She pointed to the fact that Siddiq was leading the creation of a childcare taskforce, first announced by shadow education secretary Angela Rayner at the Labour party conference in September 2016.
O'Sullivan, had previously worked with Siddiq on plans for the taskforce, but since January has not heard from the party.
"We need the Labour Party, which has shown such leadership in the past around the importance of early years, to step up to the plate," she said.
"The sector can do quite a bit, but we can't do it on our own - we're not in the House of Commons."
"I thought Siddiq was showing real potential to do things in a way that would deliver something differently - I'm saddened about the taskforce," she said.
Former Labour parliamentary candidate Denise Burke, who is also non-executive chair of Poppy and Jacks nursery and director of the Good Care Guide, said Labour leader Jeremy Corbyn's failure to appoint a shadow childcare minister made her question if he understood the importance of early years, and the difficulties faced by parents to access affordable, quality childcare.
"As we head towards September's road crash - the implementation of 30 hours' free childcare - it is more important than ever that there is credible opposition to government to highlight funding shortcomings, and to raise the negative impact of the scheme on families and many childcare providers," said Burke.
A spokesman for the Labour Party responded to the concerns by saying it was "holding this failing Tory government to account".
"We're highlighting their record of failure on issues like childcare where families face rising childcare costs, fewer Sure Start centres and parents waiting for much-needed support," he said.
"While the Tories fail parents Labour will stand up for them, and give them the support they need."
Rayner also responded to the concerns saying the party would make more announcements on the childcare taskforce "soon".
No one from the party commented on when a shadow childcare minister would be appointed.