Kattfin Ip
??? Where are you looking into it / got that information?
First of all, regular tickets do NEVER EVER sell out. It’s absolutely impossible to limit/control the number of passengers via ticket sales in Switzerland for various reasons. E.g. not everyone needs to actually buy a specific ticket for the day of travel, but simply hops on instead because of already holding some subscription-type “flat rate” pass.
Counter evidence for October 1st, departures starting from 7am:

Also, between Visp and Zermatt, the trains are expected to resume regular operations by Monday 26th August.