[Mark McLeod]

Plan for holding pressure a long time.
You don't want to drop any pressure for at least 10 minutes, preferably 30 minutes.

A match cycle is 6-8 minutes on average.
Some take longer. There are delays when schedules get too far ahead and things have to be slowed down, Head Ref match reviews or hearing of student appeals or corrected scores, robot connection issues, overly long team introductions, being on-field for Opening Ceremonies, or unscheduled VIP drop-ins.

The actual match is only 2 min, 10 sec of that cycle time.
Add a minute for you to be finished in the queue before carrying the robot onto the field.

If having a lot of trouble, then practice making foolproof connections off the robot on a simpler layout where it's easier to identify what's going wrong.
Fresh Teflon tape every time a screw fitting is tightened, perfectly square cuts on tubing ends, remove worn tubing ends, identify leaky components (dump valve, regulator, solenoid, pressure gauge, cylinders-extended & retracted), and damaged parts.