Good job getting the curve!!
By looking at your curve, he did needed the dose increase but we usually do increases in 0.25units 0.5 can sometimes be a very big increase, tonight is going to be the fourth cycle (12 hour period) on 2.5 so the depot is probably totally formed and he may go a bit lower than the other days so try and get at least a test at +2 (two hours after you shoot) before you go to bed to make sure he isn't going too low.
That being said I totally get that is really hard to get mid day tests with a full time job ( I work full time ) so get extra tests whenever you can (at night during or the weekend on the day you are not doing the curve on a day that you do not work, etc) but the tests you can't never skip are the pre shoot tests to make sure is safe to give insulin, specially in the mornings when you are going to be out all day odds are you may have to skip his insulin shot once in a while but safety first.
Getting a time feeder would help also to make sure he has something to eat during the day and that he does not eat anything 2 hours previous to his night preshoot test