Hello!
Yes, correct. After the maintenance expiry date, the renewal subscription is required with offering price as stated in our website
https://www.intel.com/content/www/us/en/programmable/buy/design-software.html#note
However, it is only done once in license lifetime before it turn to perpetual license.
Fixed license is a stand-alone (node-locked, single-user) license, tied to the network interface card(NIC) ID of the computer on which you installed the Intel FPGA software.
Floating license is floating network (multi-user) license is for users running the Quartus Prime software on multiple computers connected on a network. A license server issues licenses to computers on demand. Floating licenses are not operating system-specific. If you want to run the Intel FPGA software on additional computers, you can purchase additional seats to add to your floating license after its original purchase.
I hope this clarifies your questions.
Wani