I have been documenting this and other deceptive practices since early 2025.
Technically, it's false advertising. The Session Export feature is another example; where if the session is above an undefined threshold, huge portions of the session are omitted in the final PDF/md/docx export, again, with zero warning. This results in massive loss of user data/work/etc.
Arbitration is a serious layer to hide behind, but I think the evidence is strong enough for a class action despite.
0: I will often catch it by noticing an abrupt change in output quality. The model will degrade or change in tone, and I look down at the selected model to find, yes, it has been quietly switched to default GPT or Sonar ("best")
It is important to give Perplexity some slack where it is due, however. We know very well that to compete with all four frontier models at the same entry price, yet offer access to all of them, some cheating is inevitable. This is understandable. But they are pushing things way too far, with flagrantly, persistently deceptive and sneaky practices.
Document every instance. And save it, somewhere safe.
"Buy month to month first. The clean pattern across every angry thread is prepaid annual plans meeting mid-term cuts. A monthly plan turns a quota change into a decision instead of a dispute."
It's tempting to pay for a whole year and save a couple bucks per month. But I find that all the AI companies are evolving rapidly (month-to-month) and it's best to have some flexibility (i.e., the option to cancel at a moment's notice) in case the evolution isn't favorable.