Vitalik has announced a delay about Constantinapole. He said it will be done in January, 2019. You can look at his twitter page or follow Ethereum community.
Invest in ETH now and wait until then. Will there be swap ETH 1.0 to ETH 2.0 or will it lose all?
If ETH 2.0 has a lot of excellent features, I'm sure investing in ETH is probably reasonable, unless they do not swap. 