W42 · A plan with a spare door
Make an indoor if-plan with two usable choices. Keep a wanted first idea before the later clue.
Use paper or usual communication; no neatness, minimum length or correct-guess rule. Your helper can read the whole source and write exactly what you tell them.
Complete ordinary first source
Imaginary Lantern Room forecast, issued at breakfast, says rain is possible during the afternoon. Host Pim has two equally acceptable indoor story choices: a rain-picture story if a later note records rain, or a cloud-character story if no rain is recorded in that later view. The later weather note and Pim's actual story choice are not yet supplied. Save any wanted first idea/reason and if-plan, or mark the opportunity declined, before release.
My wanted contribution
Source, actual help and open question, if wanted
Later needs a separate grown-up release after the first opportunity. Never reconstruct an old prediction from a new clue.