Early Childhood Ireland says capacity is still a major issue for creches, which are due to re-open at the end of August.
Frances Byrne is the director of policy at Early Childhood Ireland.
She told Newstalk Breakfast: "There are three sets of issues, if you like, and Early Childhood Ireland has been saying this to the Department of Children when the announcement of the phased plan came in May."
She said these issues are health - both of children and staff - funding and capacity.
"The rest of the creches are due to re-open from late August - and that's where the third bit of it comes in, which is parental choice.
"Parental choice is not a fair way of putting it because for some parents they will have no choice.
"But we don't yet know, and we didn't know in June, how many children would come back - so the capacity issue is a really important one for creches because...funding is a huge issue".
"There has always been a challenging issue for creches when parents want a part-time place.
"In Ireland unfortunately... we invest the lowest amount of public funding in early years, so we're bottom of the EU league.
"Which means that parents, providers and staff are left to pick up the pieces: that's why we describe the sector as precarious".
"There would also be a public health concern about that because children need to come in and be in the same pod, for example.
"So sometimes the way creches manage part-time places is if two parents... have back-to-back needs, that historically has been managed by creches."
"But in cases say where I want mornings and you want afternoons, that can work out for some creches in the past - that's problematic now because of the public health advice".
"We don't know how many parents will be happy to work from home, we also don't know how many parents have been made unemployed - even if that's temporary and everybody hopes they go back.
"So the capacity issue is still a major issue.
"And Early Childhood Ireland has been saying to the department since the re-opening on the 29th of June that it's critical that it closely monitors the re-opening.
"Obviously from a public health health point of view, but also to look at these capacity issues.
"What we don't want is if numbers of children go down, then usually what happens in creches is the number of staff go down.
"And we don't want that because we know that if staff are lost to creches, it'll be very hard to get them back when Ireland is out the other side of this pandemic".
For the sector in general, she said: "It's been a tough couple of weeks... an operator in Meath, who did everything right, unfortunately had to close down because there were two different staff members who weren't in contact with each other in the creche - both community transmissions - and then three children.
"In spite of the operator doing everything right, and I think there is an acknowledgement by Government and certainly from the experts in NPHET that this is going to happen, it's going to happen in workplaces.
"And that's the thing about creches: as well as being somewhere that 206,000 babies and children go everyday, they're also workplaces where people work.
"So yes it's certainly sobering".
"Aside from that case in Meath, and we understand there's another case in Dublin... the re-opening has been very successful.
"The Government put a package of funding in place and allowed the Wage Subsidy Scheme, in a slightly different form, to continue.
"And that has certainly helped - in fact without the funding package, the re-opening just wouldn't have happened".