HTC has sent out an invitation for an event that will be held on the 1st of March 2015. That, in my opinion, is a super early invitation. It will be held at Barcelona, during the MWC (Mobile World Congress) period.
Not sure what HTC will be up to this time. Based on rumors, we should be seeing higher megapixels camera, more RAM/ROM, bigger screen size and battery. Hoping to see more leaked information on it.