A beta product is that which is still under development. It will have bugs. It will have breakdowns. It will invariably have moments where rollbacks and wipes will be necessary. If you participate in a beta, you have to accept that these things are not simply a possibility, they are a given. While these things are always frustrating they are an unavoidable aspect of beta participation. If you find such things to be unacceptable, you should limit your gaming to products that have reached commercial release.
As for emergency rollbacks, they are not by nature something that can be scheduled. The time to perform a rollback is that moment when it becomes obvious a rollback is necessary in order to resolve an error. I have been involved in several test projects in which rollbacks and character wipes were scheduled as part of the process but a game that is developed in that manner is usually subject to a full wipe before the final release.
With these two things in mind, I do not have any huge issues with how the game is being developed thus far. The problems I have seen, to include rollbacks, are not unlike every other beta project I have participated in. The one issue that I DO have regarding the most recent rollback is the breakdown in communication. As frustrating as a rollback can be for a participating player, they are all the more frustrating when they are done with no explanation. The only notice we were given was an in-game message announcing that the game would go offline for an update. There was no indication that the "update" was to resolve any issues, nor was any post made, in a timely manner, to make players aware of what had happened. Much of the angst in this thread is not so much a matter of what happened. It is more a matter of being left in the dark as to the specifics. When you leave it to the player base to fill in the blanks, you should not be surprised to see what conclusions they will arrive at.
I agree that many of us players could be more understanding of the beta process, but I feel compelled to point out that the devs could greatly increase that understanding with more timely and informative communication. It's not that I feel the devs actually "owe" us anything, but I do not feel that it is an unreasonable expectation.
Loving the game, so far.
My best wishes for the success of this project.