The company presumably filled the position b/c they needed additional help in order to meet their goals. Being willing to wait 3 months in the first place seems

The company presumably filled the position b/c they needed additional help in order to meet their goals. Being willing to wait 3 months in the first place seems like a great indication that they value you as a potential team member. Delaying further makes it hard for them to plan and likely means they will have to delay some of their objectives.