Unison plans another day of industrial action next week but will limit the strikes to schools to the north-east of the city.
Subsequent strike days are also likely to be confined geographically.
It comes as around 1000 learning assistants walked out yesterday in action which completely shut 10 schools in the city for pupils with learning support needs. One mainstream primary was partially shut.
The pupil support assistants took action in a row over pay upgrades following the requirement they administer vital medicines to youngsters with needs, in addition to their core duties, with protests staged outside the City Chambers.
Education managers have also threatened to dismiss those taking part in the action and re-engage them on new terms unless they accept the authority's compromise proposals.
The letter to striking staff from education director Maureen McKenna states: "If agreement cannot be reached, an option which may be considered by the council is to give notice to terminate your current contract and offer re-engagement on a new contract that incorporate this change. However, I must stress that this is an option that the council would only consider reluctantly."
Stephen Curran, the council's political head of education, said: "Throughout this dispute we have listened to concerns and offered to improve the pay of support staff where appropriate."
Unison branch secretary Brain Smith said: "It is a shame that our members feel bullied by the council."