I think £33k is unrealistic for a 1-2 year old car, unless it's in pretty poor condition.
Beyond that I'd assume the cars will follow a broadly typical depreciation curve. Earlier in the year was an anomaly that some people erroneously took to mean that Teslas were depreciation proof, when they aren't. Tesla are cranking them out as fast as they can make them.
What does work in a Tesla's favour over other EVs is that the software is continually upgraded, and there aren't a suite of options owners can pick, so there isn't a huge amount between the cars, although there is the occasional "big thing" that may or may not be important to people (e.g. heat pump, Ryzen, etc).