I recently put on a super and queen excluder (QE) on two full deep brood boxes. Following the advice of some threads on this forum, I put wooden strips(approx .75") between the QE and the supper to create an upper entrance above the QE. I put the wooden strips on all side, but left approx 6" out of the front side for the bees to use as the upper entrance (see picture ion below link). I also added an entrance reducer to the bottom entrance, so the bees would not have two large entrances to guard. The bees really hadn't been using the upper entrance at all for the past few days,however there has been a lot more activity in the hive the past two days (I think goldenrod flow started).. While watching the hive today I noticed several bees trying to enter through the upper entrance but there are a few bees hanging out in the upper entrance, chasing off any bee that comes close. I'm fairly certain that all the bees are from my hive and I'm not getting robbed, as I know of no other nearby hives and I never saw any honeybees before I got my hive. Is this normal behavior (bees to be guarding entrances from their own sisters)? Thanks for your help.