I'll be interested to see how you go and will be following with interest.
17kg in 90 days is a fair rate (a little over 0.7kg per week - which is respectable).
I did 29.3kg in my first 90 days but I was in a bit of a hurry as I had quite a lot to get off.
I never had any maintenance periods during my weight loss as I believe always moving forward on the weight loss front kept you motivated.
Besides one of my mantras is "there are no holidays in weight loss (or maintaining that weight loss for that matter)".
I have found that eating my meals at the same set times helpful as it gets the body's clock ticking over in a regular predictable way.
Sometimes life will get in the way of that plan but generally I was able to keep that routine going.
Also, I found it useful to have my dinner reasonably early.
Wishing you that better future that is out there for you!