You can find our OS update schedule "here." As for supporting Gigabit level speeds, whenever there's a notable update for any device we'll be sure to keep the community updated! Keep in mind though that a device that's listed as Gigabit LTE capable doesn't mean that it will reach Gigabit speeds. Many other factors do come into play that will impact performance.
Regarding your concerns with bugs, should you be having any software concerns with the device I do recommend you take it into your local Rogers Plus, they can run a diagnostic on in to determine if it's necessary to send it in for repair. Be sure to back up everything important as it may be necessary to factory reset the device.