I am the same, good connection speeds when pocketwifi says 3g, abysmal on H.
First 6 weeks (may to June) it was only ever on 3g and worked fine. Now it does what Bernard any many others does, occasionally when it stays on 3G it's better.
I use it all different times of day/night no patterns there.
I'm at 3071
I can understand your frustration with this. You should be picking up better speeds when your device is showing 'H'.
Can you please let me know whether you're using a pocket Wifi or a pocket Wifi 2. This will allow me to take a look into the network in your area and also check what may be causing this. Can you please also let me know your Suburb, as when typing in your post code a number of suburbs come up.