What happened is quite common in other industries. For example, tech sites look at the latest Apple firmware and try to find clues (
Source) (
Alternate Source) of upcoming hardware. It's common practice and Tesla's engineers are--one would assume--well aware of it. I use Apple as an example because it's another company that makes a great effort to control information flow on new products.
There is no particular inside knowledge here. We have no details on exactly WHEN a P100D will arrive. In September 2015, Musk publicly stated said that Tesla could increase the range of the Model S to over 600 miles within a year or two, immediately after the release of the 90. We
know there will be constant range increases. It's public information.
We don't know if the pack will have the same weight or increased weight, so we can't calculate range. We don't know if it'll be out at the launch of Model 3 or later this fall. Anyone following the Model S would know that a new pack would be expected eventually.
Personally and intentionally avoiding IP law, I think it would be different if information released contained completely new and
unexpected information. But to make such a big deal over another battery size? As a shareholder myself, I'd prefer the eminent P90D owners hold off a few weeks or months and purchase a (likely) premium priced P100D. We know Tesla loves pushing people to the higher end models to make bigger margins.
In the end of the day, if data inside the firmware could damage the business, it shouldn't be released or they should hide it better (e.g. encryption). Either they don't particularly care, or they now have valuable feedback on managing their firmware secrecy. Best of all, it happened with a benign leak, considering Tesla's very public comments on battery improvements.
I also think we should refrain from assuming or suggesting any actions that have occurred were malicious by either side. We can disagree with how and what we would've done, but let's give everyone the benefit of the doubt until we have evidence and not speculation.