The model I am currently using is TS-228. If I want to upgrade to TS-264C-LP8G, can I simply remove the two hard drives from the TS-228, insert them into the TS-264C, and then power on the TS-264C to access the data on the hard drives?
Based on the results from the web search, it appears that you can directly migrate by removing the hard drives from the TS-228 and then sequentially inserting them into the TS-264C.
However, the latest firmware for the TS-228 is only QTS 4.3.6
https://www.qnap.com/en/download?model=ts-228&category=firmware
While the TS-264 currently has firmware QTS 5.2.8
https://www.qnap.com/en/download?model=ts-264&category=firmware
The difference between the two is quite significant, so it is recommended to back up important data before proceeding with the migration.