If he's above 150 at PMPS and you're willing and able to test as long as may be necessary tonight, you could shoot the new 4U dose.
Or you could continue to stall for another 30 minutes (don't feed!) and see if he's high enough at +12.5 (same deal on testing)
If you give a lower dose, even a token dose, it doesn't necessarily mean you won't need to keep a close eye on him tonight because the depot is still going to be affecting the PM cycle.
Your other choice is to skip, but I hate to have you skip and lose the momentum (but if you need to, it's totally reasonable to do it)
Any time you shoot a lower than usual PS, it's a good idea to start with a +1 and +2 so if you need to intervene, you can do it early.