As I shared with you a couple of weeks ago, this would be the math to add any number of months to a date.
If I’m understanding you correctly, it sounds like you do want 36 (or any chosen number of months) separate rows. so then scripting would probably be the best way to handle adding additional rows. I would still consider a single row with date math that would dynamically update to the next occurrence of the date once the current date has passed. If I get some free time in the next few days I’ll see if I can come up with an example to explain what I mean. I do something similar in the example below, where an event can have a duration of multiple days. It only writes a single row, but the dates dynamically update every day until the duration has passed. It’s kind of a messy example, so it might be confusing to understand.