Measuring ahead

Hi,

I went for my routine midwife appointment (I’m just short of 28 weeks) and they have found that I am measuring 2 and half weeks ahead. I have to go back in two weeks so they can compare and see if it’s still the same or if have got bigger. I’ve had all my diabetes tests and nothing has come back to say that I have it. They are also scheduling a growth scan to have a look. At my 20 weeks scan, they did say my bump was all baby. My question is, if this happened to you, did they keep your due date the same or did they change it?