Bees bearding at the front of the hive is completely normal and a sign of a strong colony.
The bees are essentially working towards maintaining a steady temperature inside the hive as outside temperatures are rising and the colony numbers are high.
You may find the bees fanning their wings at the entrance of the hive as they work towards maintaining the hive and honey at the right temperature.
When your hive is bearding, you may like to ask yourself two questions. Is there enough room in the hive for the expanding colony, and are they preparing to swarm? A simple hive inspection will assist with this.
If temperatures are warm outside you can assist your bees with their ventilation by placing the corflute slider in the bottom position of your Flow Hive.
Do you have some pictures you would like to share and some explanations about your hive?
Here is a nice one from @Red_Hot_Chilipepper