[SimonPStevens]

Almost certainly not. The expected outcome is that everyone will update their software, and the old fork will die.

Unlike last year this is not a controversial fork. It's just a planned part of the network upgrade process. No groups are planning to boycott the fork.

(It's futher enforced by code in the old fork that will cause it to die shortly, so even if a group of people wanted to keep running the old fork, they would actually have to hard fork it themselves to remove the 'ice age' anyway. So it would have to be a concious act, rather than just people forgetting to upgrade)