I have only just found this forum, having been re-directed from the hummy.tv forum. My fourth forum since using Humax devices
Basically the 4000T is great, once I overcame the switch-on problem that bugged me for months, now all sorted. I previously had (still use) 9200T and 9300T machines but the 4000T is far superior. A few glitches now and again but I'd rather have a 4000T with a few glitches than not have a 4000T.
Back to subject : I too have this particular schedule display problem but there's a lot to read to get up to speed (hate the phrase but it's apt)
When my recording schedules disappear, normally leaving 5 or 6 showing out of around 45 or so, powering off and on again fixes it.
I do not like factory resets on any kit due to often having to start over again with preferred settings.