If you want to get some sensible starting numbers for your first cycle re-test your current maxes this week, knock off 10% then plum them in to the spreadsheet, which will again knock off another 10%. This will make your first cycle lighter then you could probably manage, but really use this to your advantage and work on speed and explosiveness, not just the +set volume, because in theroy you should hit that with ease.
At the end of your first cycle it might be worth then using your old rep maxes as the numbers to put in to the spreadsheet, because that would have been your theoretical start point for cycle 1.
Also dont forget, using submaximal weight training is not a bad thing at all, as long as you benefit on the points of using light weight (engraning the movement, being explosive, POWAH)
After the 2nd cycle you should easily be able to deal with the 5kg squat/dl and 2.5kg bench/ohp increases.