[help] Cat 9300 IOS version recommendations

HI all,

We have a pair Cat 9300 (advantage licensing) arriving tomorrow to replace a switch in a sort of emergency’s situation. These will the first Cat 9k we had, however once they arrive, I need to configure them into a stack and modify the existing equipment config to apply to these new switches and ship them to site the same day.

One question I have is what is the currently recommended OS version branch? 16.9 or something else? What are people’s recommendations?

Also in regards to smart licensing, do I need to open up the firewall to permit the switch to register, or can I upload a licences file or something to it?

Thanks