A Foxsat-hdr has two ways of getting the epg data.
If you press guide and you are not recording or about to record. The box downloads a new epg from the Freesat home transponder. This takes about 30 seconds or so.
Also every transponder that has a freesat channel carries the whole epg in a round robin that takes a while to get all the data. That’s the route you were using.
Once the epg is fully available a copy of the epg is stored in high speed memory.
You can display this near instantly by pressing the schedule button and then the red button.
If you try this now the whole 7 day epg should be displayed.