How does Reddit store IP addresses? I couldn’t find a clear nor recent answer.

I recently saw a local community where commenters were getting subpoenas based on IP addresses. The post was >1 y/o by time of subpoena. Reddit of course complied and released IP addresses to the court.

But that makes me wonder: what if you moved house since making the comment? What if you moved INTO a place where the IP address was used by someone else to make the comment?? Is it based on your IP at time of commenting? Is it based on IP at time of logging in to that session? Or does the IP address of all my previous comments continuously update itself based on where I log in each time? What would appropriate VPN use look like when making potentially sensitive comments?

Thanks tech buds, LLL, bye