On reflection it's easy to see why I have been growing. Just not something I had expected when weight had been the consistant for so long. Not genetically inclined to gain either. There is a definate glass ceiling for me, but will be fun to find out what I can make myself capable at that weight.
The day will govern a certain amount of what you do. There is no rule saying the increases have to be in 5kg increments and I remember seeing some enormous guys with the daintiest little biscuit weights on the ends of the bar, looking very out of place with the mass of iron beside them. Seeing them lift you could tell it was max or PB territory though so it worked for them. My PB on bench had bar (obviously), 20, 15, 1.25 and 2.5kg collars on each end, not quite 100kg but as close as I ever got. Don't dis the biscuits, they tend to get their revenge.
With how you are fealling would definately set 155 as squat 2, that leaves 3 to get it if you get too many reds or increase by 2.5 or more dependant on how you feel. Don't know how they do it there but I only had to give the weight I was to attempt at the end of everyone's attempt. Something I used to good effect. 3 is always go for broke if you have a good 2 anyway, that's why there are so many fails there. I only failed my deadlift on 3 when I competed which was annoying. I got the weight up but there was a pause on the way up, strongman allows this power-lifting is more fussy. I knew it was there but hoped to get away with it, 3 reds told me I didn't. That was a biscuit job as 2 was my known PB at the time, so was disappointing in one way but no surprise.