The Head is the first point of contact in my DD's one-form-entry primary. The email address for parents is headteacher@ (we don't know the email addresses of individual class teachers) and I had assumed that an admin would triage the emails, but it has always been the Head that has replied, and very promptly.
We've seen weak language skills a few times in TAs, eg one TA who tested a few children on spellings but who couldn't pronounce some of the words (awkward, amateur), and another TA (a 1:1 assigned to a child who is behind on literacy) who spelled 'struggled' three different ways in a single comment in a reading record.
We've also seen evidence of a lack of experience with an NQT (not knowing whether cabbages grow above the ground, or what AD stood for - in a church school).
DD (Y5) is currently a bit irritated about her teacher failing to use 'less' and 'fewer' correctly, which I think is forgivable as many adults get this wrong. I'm more bothered about her use of 'wrote' instead of 'written', as in "Come and show me what you've wrote."
I've not queried any of my above examples with the school, but I certainly would drop the head an email in your case. My DD was an early reader, and any similar mistakes might interfere with the learning, even in Reception, and they certainly reflect badly on the school.