That's tall. Have a look in your red book and there's a chart in there but I think that's around 95th centile so taller than average. 70cm is around 1st centile so quite little. Their height is hard to measure at this age as they don't keep still.
My LO got measured a couple of weeks ago and was 73cm (although it sounds cuter when you say 2ft 4) 🩵
My daughter is 7th may and 77cm she also was said to be tall. They told me this on most of my scans too
Mine got messured few weeks ago and was 70cm and I think she is tall