Massive and aggressive downside Euribor option trade

Market contacts note a huge bearish position in the Sep19 expiry via 99.50 puts that have been bought a whopping 100k times from 4 up to 4.5 ticks. The underlying 3 month future is currently around 99.930, so a very hawkish punt/hedge for rates at 0.50% vs the implied 0.07%, albeit at least a year after QE ends or 9 months assuming the ECB opts for a more tapered unwind from Eur30 bn over 3 months to the end of this year.