"青梅竹马" is a Chinese idiom which generally means two people who have known each other since they were young, often used to describe a relationship between a boy and a girl. The phrase "是消防员" means "are firefighters". "一季樱花未增删" seems like a poetic description that could be translated as "a season of cherry blossoms without additions or deletions", perhaps symbolizing something unchanging or eternal.

Putting it all together in English might look something like this:

"Childhood sweethearts who are firefighters, a season of cherry blossoms without additions or deletions."

However, the sentence as it stands doesn't form a complete thought or a coherent story. It sounds more like a collection of phrases or ideas that may need further context for a proper translation or interpretation. Could you provide more context?