ASA and U-trip Mens Slow Pitch - Changing Game Ball

[Larks]

Whats up Blues? I usually post a lot on the basketball side of this forum since thats my sport but I do play softball. Mostly ASA C and U-trip C. I'd like some feedback on changing the game ball out.

Most of the fields we play at, we are required to provide our own game balls. Each team gives the other a ball to start with and if there are any home runs or unretrievable balls hit out of play, the batting team throws in a replacement.

Last night (ASA) we had a ball hit well out of play onto another field. I asked the umpire if we could throw in a replacement (also brand new) ball since the other one was out of play and further had been used for about 4 innings. He denied my request because the original ball "was coming back in".

What is the rule for changing the ball out? Does the ball have to go out of play? Can a team change the ball out before an at-bat starts? Or, does the team have to wait until the ball cant be retrieved and / or the start of a new inning.

U-trip and ASA please.

Thanks