As far as I know, only the Ing-Diba finances during the probation period, no other bank does. That was my knowledge about 2 years ago. I have no idea how it looks with a fixed-term contract. But I consider a fixed-term contract even worse than a probation period. Personally, I would never enter into financing because neither a contract extension nor a probation period always has to do with performance. You just have to not get along with each other, and the end is preprogrammed, by that I mean the personality factor.
EDIT:
Just something to think about so it doesn’t become a rash decision for you: verbally, the development was promised to us by the municipality in summer 2017. In the contract at the notary, December 2017 was assured, and in the end, with surveying and all parameters to meet the bank’s disbursement requirements for the home financing, it became July 2018. We started building a week ago.
So take your time and pay for the plot in cash and reserve a general contractor, otherwise it won’t work out to start building in 2019. If YOU were to sign now, you would be put off until late summer 2019.