Well technically there can't be unlimited EC before M3 b/c the supply of FCT required to generate the EC would be exhausted at some theoretical point. But I think you're asking about whether or not the servers currently running are capable of handling a much larger amount of "factomization." I don't know about that but my strong suspicion is that they can. My understanding is that the limits of the tech ATM don't have to do with capacity so much as customization / userability / etc., but someone can correct me if I'm wrong ...