What I'm asking you is, what criteria will you use when it is no longer too early? At some point it won't be too early, but none of us know what the criteria are that you will be using. It's hard, given the fact the Chief Electoral Officer has just prepared a report, released I believe it was yesterday or the day before, stating he will need extra time to deal with the referendum process. He'll also need extra time to deal with any electoral boundary redistribution that might occur as a result of this process.
Effectively as you take more time, you start precluding options. It's not hard to design a system so that only one option is left, which just happens to be the one your Prime Minister has indicated he prefers.