I'm having the same issue as well! I do not have a way of going back to the home screen or anything. If I hit the back button it takes me to the detailed summary and then back to the page to upgrade to premier. Very frustrating as my return is finished but it looks like I'll have to restart it. 

I still can’t get back to tax home. Is the  forms now compliant with CRA? It is now 3 weeks since I was unable originally to complete my return due to the residential flipping aspect which is not the case

I am using TurboTax online version and I am having the same issue. I can no longer go back to the home screen. When I hit the back button, it keeps sending me back to the summary screen and to the "upgrade to premier" screen I can no longer finish my tax return. Also, where can I find this option to say no to property flipping? I haven't seen this on the Tax Home page.

On the Tax Home page, search for Residential Property Flipping. You can say No to property flipping there.

Please note that even if you are just selling your principal residence, you will need to use TurboTax Online Premier.