The next ETH 1.x / Core Dev in person meeting is confirmed for San Francisco at the end of January.
While looking at the Istanbul roadmap timing, May 17th is the hard deadline to accept proposals (EIPs) for the Istanbul network upgrade in October 2019.
I propose to hold an ETH 1.x / Core Dev meeting the day after ETHCC in Paris, which would be March 8th. This can be an early review of what people are planning to propose / have proposed already, get talking with implementors, and so on.
It may also be useful to host an ETH1.x (/ ETH2 ?) AMA during either EthMagicians Council of Paris 2019 or at ETHCC itself? Similar to the one in Prague.