I hope everything goes OK

Life is always unpredictable. Never goes in a straight line

We had somewhat a similar plan. Not selling house and buying another but building another house in another town then remodelling our current house. A number of factors complicated and delayed building the 2nd house, so we decided to start remodelling the current house first, and when done, we can go back to assess the situation with the second house. As it seems, this plan has a number of advantages, and will be less stressful. So you never know what's best.