Islanders’ Sebastian Aho gets back in lineup

Sebastian Aho is a quick study, anywhere and anytime. He learned on the fly as an emergency callup, learned some more just by watching during the past week and learned enough to find his way back in the lineup Monday night. He played in place of Dennis Seidenberg.

“I enjoy every day that I’m up here,” said the 21-year-old defenseman who was promoted from Bridgeport Dec. 28. “It was pretty hectic in the beginning. I didn’t know if I was going to be up for one day, two days.”

The Islanders have kept him around, even when they did not play him. He used two healthy scratches last week as a sort of reading period, getting perspective from the suite level. “I like to watch Hicks and Leddy,” Aho…