Hackers will get the payout within a week of submitting the zero-day exploits along with a valid working proof-of-concept. The price for zero-click remote code-execution exploits in Windows and Android has been increased to $1.5 million for persistent iOS jailbreaks that can be executed remotely without any user interaction (zero-click) Zerodium also doubled the price for remote code execution (RCE) exploits that target secure-messaging apps like WhatsApp, iMessage, and SMS/MMS apps.
Source: https://thehackernews.com/2019/01/zero-day-exploit-market.html