Basically, the rule of thumb is a 30 minute window both before and after any SFQ practice, both active and meditation. The reason is that all of your energy is going to the digestion system after eating (or during). That is slightly undoes what you are wanting to happen with your SFQ practice, where the energy is opening channels and storing in lower tan tien (digestive system is NOT only the lower tan tien)
But again, it is is "good, better. best". This rule of thumb is "best". But for many people due to their schedule, it might be "better" for them to have to do SFQ right before or right after eating. That way they can practice more consistently.
And, again, since it is "good, better, best", though 30 minutes is "best", it might be better to do do 15 minutes than only 1 or 2 minutes.
20 is better than 15 and so on.
Hope that helps.
