Hmm, so for me it’s not necessarily the loan amount in relation to the current income causing concern here (120-122x). That is also by no means insignificant and not necessarily something all banks do (but it also doesn’t sound like "this has never happened before"), but rather a bit the question marks behind the incomes.
I think building during family planning is generally very risky. On the one hand, at that moment usually (except for the "man earns 10k net solo" people) the income situation is not great and on the other hand the development is unclear. If for some reason re-entering the workforce takes longer, then suddenly things look very very very tight. That means I would definitely play through some scenarios before building exactly in that situation. The optimal thing would probably be to postpone the house project until you know a bit more precisely where you stand financially (E.g. both working again or alternatively also knowing for certain that it’s not the case) and keep saving until then.
Practically, I can also understand if you don’t want that, but hmm. For me, quite a lot of flexibility in the financing would be important then, and then the question is whether the banks will even go along with that in this form.