Some of the purchasers of the new Surface Pro are experiencing hibernation issues. With a firmware update, Microsoft is now trying to solve the issue. Yesterday, the company released a Surface System Aggregator firmware update which revises system power reporting.
The update history page for the Surface Pro does not include any further information, noting that Surface System Aggregator version 233.1763.257.0 “revises system power reporting” and improves reliability.
Nevertheless, the update will very likely include a fix for the hibernation issues that users of the new Surface Pro began reporting in early July.
Hopefully this fix solves the problem!