There's now a travel waiver in place. Just received this email from United:
We're not going to let runway repairs at SFO slow you down
We have a hard hat heads-up for you:
From September 7–26, our friends at San Francisco International Airport (SFO) will have a major runway closed for repairs. This could lead to delays, but we're here to help!
If your plans are flexible, you might want to consider flying a day earlier or later or connecting in a different city. The good news is that we'll waive the change fee. Visit united.com or use the United app to check your flight status and find more information about your options on our Important Notices page.
Thanks for packing a little extra patience!