Double bag question

[Hoosier_Dave]

BR hits to right field. BR rounds 1B heading to 2B. Throw comes into 2B. BR retreats back to 1B. 2B throws to 1B to apply tag. BR (now runner) runs back to 1B and steps on orange bag only before tag is applied. Tag is applied when runner is standing on orange bag. I rule safe; coach questions. I told coach in this situation, that it's one big base.

I checked the rule. The rule was changed this year and added the orange bag on a pickoff play. I deemed this as a pickoff play.

Partner says that I should have ruled out because runner must establish on white bag and orange is only for BR going to 1B. Once BR reaches 1B, orange bag can no longer be used. We had this discussion VERY discretely.

Who's correct?