The Cherries sealed promotion to the second tier on Saturday with a 3-1 victory over Carlisle in front of 9004 and Mitchell revealed they plan to build a fourth stand in time for the big kick-off in August.
"I would like to think there is every chance to get it ready for the start of the season. We just want to get it done," Mitchell told BBC South Today.
"Our main aim is to get another 3-4000 in the stadium. We've got to do our bit and get that capacity up.
"We want to replicate the North Stand. To take it on further we will need different planning permissions, which takes time."
Bournemouth could clinch the title with victory at Tranmere this weekend before thoughts turn to life in the Championship.