As many of Scotland's 4,000 nursery nurses took to the picket lines, local authorities accused Unison of trying to renege on an agreement signed four years ago. The deal replaced the old APTamp;C conditions, backed local pay for council staff and ended national settlements for nursery nurses.
Union unity was coming under further challenge as another three authorities - West Lothian, Angus and Orkney - moved closer to sealing deals on higher pay and better career structures. This would bring the number of authorities to reach a settlement to 11 out of 32.
Three out of four nurseries in West Lothian, for example, were said to be operating despite the action by Unison. Glasgow, with a quarter of the total workforce, remains the key battleground.
Local authorities stepped up their response to the dispute following a meeting last Friday at which council bosses reaffirmed their determination to settle locally and ordered a "more robust" counter-action against Unison.
Lynne Dickson, the employers' secretary, this week went further by flatly dismissing any suggestions of an agreement at Scottish level. "We have no scope to do it. The national agreement Unison signed up to said that pay and regrading would be determined locally. That has been the case for four years," Ms Dickson said.
"They have members across the spectrum of local government and whether it is social workers, classroom assistants, librarians or housing officers, pay and regrading are going to be determined locally."
She added: "Unison knows there can never be a national agreement. If they are indicating that there has to be some other mechanism for settling pay, why do they not say that? They know it cannot be settled under the current bargaining machinery."
The Convention of Scottish Local Authorities says that it drew up a new framework for nursery nurses last year, based on three separate job evaluations, and has been using it as a guide for individual authorities.
It maintains that Unison refused to take part.
Ms Dickson said that starting salaries within the framework began at pound;14,000 and rose to pound;18,000, depending on the length of working year.
It appeared deals struck by councils and union branches were within the range. Most nursery nurses who work in nursery schools and classes were already at the top of their scale at pound;13,896 and their pay would rise by almost pound;1,000 to pound;14,825.
Authorities say there are few problems with recruitment, that staff are better paid than in the private sector and south of the border, and have already been made a special case by the framework review which includes almost a year's backdated pay rise.
Both sides accuse the other of moving the goalposts in a dispute that goes back two years. Joe di Paola, Unison's Scottish organiser, said that nursery nurses currently have a Scottish-wide grade that was established 16 years ago but increased duties and responsibilities, such as the 3-5 curriculum and national standards for early years education, had changed the nature of the job.
Mr di Paola said: "The local government agreement means that pay and conditions will be locally established after a job evaluation survey. No council has ever done one. Most councils are not in a position to do one.
"After asking twice for the implementation of these to be delayed, Cosla has recently written to trade unions indicating that it will not now be implemented by the target date of March 2004. Because of this, Cosla wrote to local authorities telling them that it was legitimate for the trade unions to submit a national claim for nursery nurses."
Mr di Paola accepts that nursery nurses were not exempt from the agreement but insists their pay claim should be dealt with now. He says the Cosla job evaluations were "deeply flawed" and did not address career structures.
Authorities believe the Unison drive on regrading follows the post-McCrone deal for teachers and dissatisfaction among many nursery nurses that classroom colleagues can be paid double for what is often similar work.
Many nursery nurses, now being retitled early years workers, are further incensed that the national regulation to have a teacher in a nursery has been scrapped by the Scottish Executive, against the advice of the General Teaching Council for Scotland. They see this as a move to cheaper labour.
Mr di Paola said there was no intention to bring nursery nurses within the teachers' framework. "Nursery nurses are not teachers and do not want to be them. That is why the claim for the nursery nurse grade stops at the very bottom of the teachers' national grade."
The yawning gulf
* Cosla: "Forget the figures, this dispute is really about Unison wanting nursery nurses working 39 weeks a year to be paid the same as nursery nurses working 52 weeks a year - and again regardless of the nature of the work they are actually doing. That is blatantly unfair."
* Unison: "Most 39-week nursery nurses work 32.5 hours per week, their hourly rate is pound;13,896 divided by 39 weeks equals pound;356 per week - 356 divided by 32.5 equals pound;10.96 per hour. Cosla based its recommendation on a 35-hour week. If we use the same calculation for the new rate and hours we get pound;10.86 per hour. Cosla is suggesting a salary that reduces nursery nurses' rate by 10p an hour."