With 11.5 hours of time available (including dinner break), I'd go with this structure:
PLO, 30-45 players
T40K stacks (400bb)
30 minute blind levels
L1 50 100
L2 75 150
L3 100 200
L4 150 300
20-min break - remove T25 chips (2:00 hour mark)
L5 200 400
L6 300 600
L7 400 800
2-hr dinner break - remove T100 chips (3:50 mark)
L8 500 1000
L9 500 1500
L10 1000 2000
L11 1500 3000
20-min break - remove T500 chips (7:50 mark)
L12 2000 4000
L13 3000 6000
L14 4000 8000
L15 6000 12000
L16 8000 16000
15-min break - remove T1000 chips (10:40 mark)
L17 10000 20000
L18 15000 30000 *** EOT, 30 players (11:35 mark)
L19 20000 40000 *** EOT, 45 players (12:05 mark)
L20 30000 60000
L21 40000 80000
L22 50000 100000
PLO events typically end no later than when a total of 40BB are in play, and often much sooner (100bb in play heads-up or three-handed is not uncommon).
If 1:30 a.m. is a hard cut-off, you might want to drop the blind level times (with 45 nitty players) to 25-minutes after dinner break, saving 50 minutes or so (30+ players should be fine). Worst case is that it ~might~ run 30 minutes long past your 1:30 end time (with 40+ players).
But if everybody entered plays PLO Gunnar-style, you may not even get to the T1000 color-up.
Assuming T40K stacks, 45 players, and a large available quantity of T25/T100/T500/T1000/T5000/T25K chips, I'd go with 12/12/5/6/6 starting stacks:
540 x T25
540 x T100
225 x T500
315 x T1000
284 x T5000 (includes 14x for color-up of T25/T100 chips)
16 x T25000 (color-ups for T500/T1000 chips)
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1875 total chips
It can be done with just 1,505 chips, using 8/8/4/7/6 stacks and T25K chips for all color-ups:
360 x T25
360 x T100
180 x T500
315 x T1000
270 x T5000
20 x T25000 (all used for color-ups)
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1505 total chips
Note that including T25K chips in the starting stacks is NOT advised.
Good luck sir!