deeredale,
A late welcome!!
Glad the pup is doing well for you..
The way I understand is that 100 rounds is the reccomended time for the spring change..
I was in on the "early" recomendation of "many more"..

I do not shoot my carry pup a whole lot,has been good for me after break in,so I do not worry a lot about the change..
I think I have averaged between 200-250 before a change..
This is just me..
I have not had a problem before the change,or after..

Feed the pup what it likes to eat,and that will make it happy!!

Once again,Welcome...
Brenden