becaroo Yes. Well, if you don't then the baby will be thirsty and drink more milk which will fill them up and then they won't want to eat iyswim.
It isn't harmful not to unless you are deliberately denying ff then they could be at risk of not getting enough fluids.
Also, it depends what you are feeding, i.e. if pureed apple has more fluids than bread. It is just sensible to 'offer' water.
With DS, the HV advised giving cooled boiled water until a year. However I researched the subject and concluded that there was no harm in giving water out of the tap (can't remember references sorry), so surprise surprise I chose the easiest way. Having said that, I think I started with cooled boiled water until 6 months.
And bec What reason do you have for dreading the meeting? Do you feel you will be challenged, or are you worried about criticising the teachers?
Teachers CAN be defensive about their teaching, but generally they are not. The whole world criticises them so they probably won't even notice. Mostly, they appreciate parents that are trying to be involved in the education of their children. Good luck!