Your midwife should have informed you at 24 week appt with her that 28 week onwards, she will be measuring your bump every 2/3 weeks dependant on what hospital you are with, they do it when you are led down :)
I just had mine measured at 25+4 at the midwife appt and measured 25.5cm! X
I had my bump measured for the first time at my 28 week appointment and he was measuring 27 weeks but then I was unwell at 29 weeks and had a scan and he’s actually measuring 30 weeks!
I think it depends where you are based and your midwife. I never had mine measured this pregnancy or my first. I believe the measurement is not to be very accurate as well.
I had mine measured at 24 & 1 weeks and have it being measured again tomorrow at 28 & 1 think it all depends on the midwife unit
So I had my bump measured first at my 28 week midwife appointment ❤️