Almost that time, unfortunately. I use Marvel Air Tool oil for afterrun oil, the usual internal saturation. It works well. I have noticed my hi speed needles are getting hard to turn and suspect the O ring is swelling. Should the needle housing/needle and O ring be wet with after run oil when in winter storage? Does this stuff cause the rings to swell? It's very frustrating because these O rings are very difficult to find. What do you all use and the successes you have? Thank you.
Bill

After run oil is injected directly thru the carb or into the exhaust port so it doesn't directly impact the o-ring. I always run the engine dry at the end of the season and then oil it well for storage.
A supply of o-rings might be had from different sources but the old school method of a fuel line sleeve over the needle valve and the shaft it threads into might be the answer to a new air seal.

I store engines in a heated basement. In the summer I run a dehumidifier. The RH is always below 50%. I run the engines dry at the end of each flying session with no after run oil or storage oil. Rust has not been a problem and some of the engines are over 20 years old.

hi
this is almost the same approach as I do it. No problems at all.