If there is, no one knows. Then again, I read that people in RVs that change locals frequently and have guide issues with their local channels found that unplugging the receiver for ~30 minutes seems to force some updates.
Totally agree with the no rhyme or reason lol. Occasionally I see on the TV Activity page where one tuner is updating the guide. This is while I'm watching a program, and most times, not all, while recording something at the same time. That tells me it doesn't need to be in any particular state to update, but maybe being in standby "can" somehow expedite it. Thanks!