DepDiver was nice enough to Pm me some information, and we discussed it some. Thought I'd post this follow-up...
We drove a different route, so our 1300 foot increase in altitude was more gradual, nonetheless - we rounded up to 2000 feet and approached the arrival as if it was a sudden increase. Based on Padi's altitude training and RDP Air chart - we presumed we were at Table D, and while we did not have a full 4:19 hrs after arrival to clear totally, we were there well over 1:19 hrs to Table A. We added 3 minutes Residual N2 to our dives for the rest of the day.
I like Oceanic Computers, but the barometers are accurate only to within 1,000 feet, so I advised my buddy that what his puter said could be off - reading the dive plan for a 3,000, 4,000, or 5,000 foot dive. I don't recall what they actually said when activated, but we went with 84 feet adjusted to 110 feet, 16 - 3 = 13 min BTime for the first dive.
Our puters were all in the Green for the entire dive, and we did a 1 minute Stop at 42 feet and 3 minutes at 12 feet, but we presumed Padi maximum Table M after a 110 foot dive, followed by 1:26 hr SI, yileding B with 10 minutes allowed - 3 minutes from start, so only 7 minutes BT. We went to the bottom on the second dive, then started a gradual multi-level up, as mostly my buddy needed practice swimming and feeling confident. Again, puters were all in the Green even before the 1 minute at 42 feet and 3 minutes at 12 feet. Next day, we started with a clean slate, no Res N2, and planned and dived similarly.