Try this...
Look in the Hub settings and navigate to the Configuration Data page. What numbers are in the Max Data Transfer Rate boxes for Downstream and Upstream data. These ar in bps - not Mbps. If the upgrade went through the will start 1xxxxxxxxx... if it didnt they will begin with 6xxxxxx..
If its gone through - first do a pinhole reset as per... First make sure the 2 passwords on the Hub sticker are still there and legible first ! Disconnect any ethernet cables from the Hub (leave the coax connected), and then with the Hub still "switched on" throughout, press pin in firmly with paper clip/SIM tray tool or similar "thin thing" and hold it firmly for at least 60 (a timed sixty) seconds, release the pin, leave for 5’ to stabilise - dont manually switch it off at any time. Passwords will reset to those on the sticker. See if that sorts it
If not... are the speed issues only evident on wifi connections or do you see them at the same times on devices connected on ethernet cables? If you don't know, can you check to help diagnose whether it is just a wifi issue or it could be network connection/Hub related?
And to test on ethernet - can you do it this way.....
As you expect ~1GB then connect a 1GB enabled computer/laptop, with up to date drivers, via a NEW and working Cat5e/6a ethernet cable, directly to the Hub which you have put into “modem mode”
(
https://www.virginmedia.com/help/virgin-media-hub-modem-mode ).
This ensures that NO other devices are connected
Test speeds at
https://speedtest.samknows.com/ - try on 2 different browsers.
If they are still low – boot your device into Windows safe+networking mode - to disable any potentially interfering software - and try again.
There are many posts on here (I have a list of ~30!) where QoS software, unknown/flaky software, old network card drivers, corrupted browsers, bad cables or other connected devices are limiting speeds on tests.
Report back what that gets.
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John
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I do not work for VM. My services: HD TV on VIP (+ Sky Sports & Movies & BT sport), x3 V6 boxes (1 wired, 1 WiFi, 1 on PA) Hub5 in modem mode with Apple Airport Extreme Router +2 Airport Express's. On 250Mbps, Talk Anytime Phone, x2 Mobile SIM only iPhones.