There are two things happening. both providers and customers are getting vaccinated and back to normal. Unfortunately, the guys have been holding their wallets and their loads for a long time and are probably over visiting to compensate.
It might be tough, but schedule an off peak time where the provider is not rushed to make as much money for herself, the house and prevent an impatient customer from leaving.
Take a shower, head over and just do the 1/2hr session. If she manages to short you for a 30 minute session, then you might start raising the red flag.
I will tell you I have visited a couple of spas over the past 5 years. In that time I have had absolutely amazing sessions that lasted 45 minutes and have had absolutely horrible sessions that have lasted over an hour.