Using the AMS when first starting to use they suggest 2-3hrs. Your bladder may have shrunk and you will need to stretch your bladder gradually.
If you have a tight ballon and you try to blew it up, it tends to be more difficult. As you blew it up gradually it stretches.
Your bladder after disuse, leakage, is similar and the device (artificial sphincter) can hold so much before you leak.
When I had it activated I drove from Cleveland home, which was 3-4 hrs. I had to stop after about 2.5hrs, my bladder felt full and I had to go.
That's the other area, prior to sphincter, sometimes, I couldn't tell if my bladder was full or not.
I still have some leakage, don't pay attention to bladder or accidentally activate button, the system isn't perfect but comparing to prior I am 150% better.
Tom