I would have a word with teacher tomorrow, in that case - tell her how difficult DD is finding it and ask if you can come and see her after school once a (week?) (fortnight?) - if DD knows she will still see her it might ease the blow.
really? i just say 'it is sad, darling isn't it' and turn the conversation round to the new teacher who is probably going to be just as nice, maybe even nicer, and what fun you'll have in the big school - wow they have a different playground and get to....'
i'm not sure i'd be prepared to wheel her off to the infant school whilst the teacher has got her hands full with a brand new class who are having difficulties settling in, and mummies who need to talk to her...
I remember my mum saying that my sister was heartbroken on leaving her first teacher, the teacher gave her a teddy from the classroom to keep over the holidays and return at the start of the new year - so that DSis would know she would see her again.
Not regular visits, but that guaranteed one visit.