how long should I feed.
There is no categoric answer to that question.
As long as, and if, necessary. But only if necessary.
Most colonies do not need feeding at all. They never get fed in the wild. Those bees in the wild which do not collect, or do not have, sufficient stores would perish. Genes gone from the pool. Survival of the fittest, etc, etc.
Your reading source is rubbish. There will almost always be a honey arch above the brood. There will be no open brood after about a week, so no more larvae to feed.
So it quoting 'for the next few weeks' is absolute garbage. One week, perhaps - and quite likely not necessary. After one week, there will, again, be adequate foragers to maintain the colony. Read it carefully, too; it also says 'may' need feeding. That most certainly does not mean 'will'.
IF, on the other hand, they decide to swarm while there is no income (as in forage, not any shortage of bees), and stores are insufficient to last until the next inspection, you would then consider feeding. 'Consideration'would take into account not only the current level of stores but also the weather and flow conditions. If it warm and dry and there is plenty of forage, you would not feed unless very low on stores. Application of common sense, really. You are the beekeeper and bees do not read books.
Autumn feeding is entirely a different matter. We are, as yet, nowhere near autumn.
a). People should read everything carefully, and b). Those that give out information should get it right.
There are too many that don't read properly/carefully, and also don't think of actually checking out if what is printed, or said, actually makes sense.
