Due to the storm damage the trains on this line cannot run past Meiringen. You board a replacement bus there for the drive to Interlaken Ost. The following notice is on SBB (even in the English version):
Wegen des Bahnstreckenunterbruchs gibt es nur begrenzte Plätze in den Ersatzbussen. Wir bitten Fahrgäste, alternative Reisemöglichkeiten zu prüfen und auf Reisen über die unterbrochene Bahnstrecke nach Möglichkeit zu verzichten.
Basically, they are saying that seats on the buses are limited and you should consider alternate routes. That means route through Bern (or Olten) instead of taking the scenic route. I do not know if there is any estimate as to how long this will continue.