I get this same error when running: truffle migrate. Here is the full error from the console:
Jeremy Mappus
11

This is an exception error.

It is probably this line

const startTime = web3.eth.getBlock(web3.eth.blockNumber).timestamp + 1

try making it startTime longer in the future, for example:

const startTime = web3.eth.getBlock(web3.eth.blockNumber).timestamp + 10 // 10 seconds from now