Not much you can do to change the firmware - a restart can provoke the hub to check if an update is available, but roll outs are always phased, so unless the new version is being distributed to your area, no amount of restarts will help. Best approach is to leave the hub to its own devices, and it will find and load the latest version when it is available. No idea what is latest, but mine's on 9.1.1802.613 and I'd guess that will roll out to yours in due course.
Having said that, I've been playing CSGO very happily with version 610 for months, so if you have a noticeable latency problem then you most likely have a line problem. Post the Upstream and Downstream stats from your router info pages (you don't need to log in) so we can see if there's an obvious problem, you may also want to set up a broadband quality monitor at thinkbroadband.com, let that run for a day or so, and post a link to it here.
If it is a line quality issue, VM field ops staff will probably need to fix it, but lets see what the checks above reveal.