More SaaS apps should do unlimited duration usage-based free trials. If your product is good, you want to maximize the chance of people actually getting to the aha moment before hitting a paywall. https://twitter.com/philfreo/status/1548704988100173825
Biggest reason to do strict time-based trials is to create a sense of urgency. Especially if you have a real sales process. But many apps would benefit from giving users more of a chance to see any value before getting locked out. Especially if their process is fully self-serve.
Even if you do have a time-based trial, you should give expired trials and canceled customers another chance later automatically. We did this at Close and it helped at lot: https://twitter.com/philfreo/status/629803820944506880