We’ve seen instances in the past where an update to a device has caused problems, although usually this can be fixed by issuing another update that addresses the issue. However it’s not often that we come across updates that actually render the device unusable to the point where they might need replacing.
Unfortunately that seems to be what happened to some Surface Pro 4 owners, in which according to a complaint posted on the Microsoft forums (via PhoneArena), some users were saying how their devices have become unusable following a firmware update. For some, this has resulted in the touchscreen not responding, while others claim that they are unable to turn on the device, and restarting the tablet is taking considerably longer than usual.
Microsoft has since responded by saying that they are investigating the issue, but in the meantime it appears that users who have been affected by this problem are able to get a replacement unit. This doesn’t seem to be an official move as it requires calling Microsoft and asking to speak to a manager, where you will need to mention the community page that the problem is listed on, after which you might be eligible to get a replacement unit.
It is possible that a future update will fix the issue, but in the meantime until Microsoft releases said update, perhaps you could consider requesting for a replacement.