Hi -
Retired male TA here. I worked over twenty years in primary schools, mostly as a TA, but also as a voluntary helper.
There is so much more to school than just literacy and numeracy, and if she is happy and seems to be coping with all the other activities, then I don't think you need have any worries.
It shouldn't take a competent teacher very long to assess her abilities.
These twice weekly 'parent/child' reading sessions: are these voluntary, or did school suggest you went to them? I have known similar sessions, but they were 'family learning', where the parent, as well as the child, needed support to improve reading and writing. Judging from your 'post' you certainly aren't in that category! Or did school think it might help you BOTH to settle in by attending these groups?
Do you have a general 'feel' for how she copes with: numeracy; writing; confidence, speaking and listening; PE & games; arts & crafts, music, drama, dance etc. Some of these things are more a product of a child's home life and previous experiences, rather than what they have been formally 'taught'.
I will try to come back tomorrow with copies of resources for literacy and numeracy, that I often pass on to MN parents. In the meantime, if you can answer some of the questions I have posed, it will give me some idea of her interests and abilities, and we will see where we go from there!
I assume there aren't any major behaviour problems, as you haven't mentioned anything like that; but sometimes a lot of 'moving around' or travel stress can unsettle a child.