Thank you Genty for the link to the statement. So it is to be 4 to 12 weeks for the Astra-Zeneca and 3-12 weeks for the Pfizer. It also says -
"The JCVI has also amended its previous highly precautionary advice on COVID-19 vaccines and pregnancy or breastfeeding. Vaccination with either vaccine in pregnancy should be considered where the risk of exposure SARS-CoV2 infection is high and cannot be avoided, or where the woman has underlying conditions that place her at very high risk of serious complications of COVID-19, and the risks and benefits of vaccination should be discussed."
PS - Some people can't go to links, or don't want to, so it is useful to add a note of what they say, as well as the URL itself.