Mortgage for buyer of renovation property

We have just bought a house that we are planning to do up and then sell on. Doing it up is likely to take a couple of months.

I found some information on the internet that worried me - it said that a potential buyer of the house, once it is done up and we are selling it, will not be able to get a mortgage if we have owned the house for less than 6 months.

Can anyone advice me if this is true - as it could make selling the property so much more difficult.

Here's hoping that it is not true.