Latest news seems to indicate that Softbank is considering investing at a ~$40B valuation.. considerably lower than the $69B number floating around. And although it is probably just a negotiation tactic, they claim to be considering an investment in Lyft instead.

https://www.recode.net/2017/8/7/16110020/benchmark-softbank-...

https://www.cnbc.com/2017/07/31/softbank-talks-to-invest-in-...

To elaborate, iirc Softbank wants to buy at a 30% discount to the latest topline paper price (which is entirely fair).