We did the EBPC out of San Diego on Wonder (which I assume you're doing too...). It was pretty efficient and we were on board before out designated time. They didn't get wrapped around the axle about specific times.
Port arrival times aren't enforced. It isn't a fun terminal to sit around in, I wouldn't get there super early. Security used to be very very slow but it has improved dramatically. On our last cruise our group of platinum cruisers all arrived at the terminal around 10 and we were on board around 1130. We've cruised from SD 6 times with DCL, as sliver, gold and platinum-never saw PAT enforced.
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