Though you can still use and maintain concentration on a spell cast prior to going into Wild Shape correct? (Example: Call Lightning)

— Jibberjabberwocky (@EvanW256) January 28, 2019

Your ability to concentrate on a spell isn't inhibited unless a rule says it is.

For example, Wild Shape says you can't cast spells. It doesn't say you can't concentrate on a spell you already cast. #DnD https://t.co/qkcZUZQHbu

— Jeremy Crawford (@JeremyECrawford) January 28, 2019