Maybe Bitmain thought that ZEC and others might fork by end of the year and hence only planned production until Oct or so? Which now seems a mis-calculation.
Maybe this! You can expect everything from Bitmain. But at the same time I also highly doubt this is the reason why they don't plan to produce it. Bitmain will have more chips if they need, that's not a problem for them. Maybe they hang on these coins because they already made great profit while mining silently and now are working on different things. Also we need new antminer for bitcoin too, current one isn't profitable. Maybe it's now their priority.
