The established time is the shortest of the 3 run validations.
For DHT and CHT, you can go about this 2 ways. Record the times that soiling, cleaning, and then use were done during cleaning validation activities. Then calculate the CHT and DHT.
Option 2 is to predict what CHT and DHT is required from a review of your manufacturing practices. Then design your study to match these. Record times soiled, cleaned, and then used, and make sure that they meet/exceed the CHT and DHT.
Option 3 is to establish a CHT and DHT time, but also to realise that this CHT and DHT might increase with further data and support. In this case, validate a CHT/DHT initially, but then create a proceedure to review data, hold product temporarily until data can be reviewed, if ever the CHT or the DHT is exceeded. This would be “continual review”. As your process matures, and you collect and analyze more data, then your CHT and DHT change accordingly.