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I'm sort of thinking out loud so if it doesn't make sense...just let me know. Some of this is general ideas becuase it's tough to say, for sure, without seeing pics or knowing bf% but...I'm thinking you must have some decent muscle mass, for your stats and seeing some seperation already and maybe that 155 lb goal will be realistic. So given that, you have 17-19 weeks to go with a target of 17.8 lbs to lose (again, it may be slightly higher).
That gives you a target of 1 lb or slightly more to lose per week, although most don't count that last week before show time, but you get the idea in how to look at it.
The one thing I'd really watch is your calorie level. If you're really carrying the muscle mass I think you are, I think you are starting out a little bit low at 1720. Especially if you find you're stalling early on and having energy issues. I know you've just gone back to work, some other stressors too and tough to say if it's all diet related. There is always some diet pain and low energy that comes with prep but it's quite a ways out to be feeling it already. The danger is you will have to lower calories further, energy levels continue to drop and you'll still have several weeks left and not a lot of room to move when you stall out.
There's a couple different thoughts on that. You can bump up the overall calories a couple hundred and take advantage of the time. You could structure at least 50% of your carb intake to fall around your lifting sessions, both before and after. That will help with energy there. The other thought is the structured refeed. Different than a cheat but a planned and measured increase in carbs once a week/ twice a week...timing again relates to bf and timelines. Some people do that over one meal, while others will do it over a day but find that it will keep things moving and helps with the energy levels too. I can give you more info on how to set those up too if you go that route.
Just a few thoughts to mull around for ya!!
I think you're in a decent position though and have the time to keep the diet reasonable vs that intense drastic cut. So keep working hard!! You're doing great!
That gives you a target of 1 lb or slightly more to lose per week, although most don't count that last week before show time, but you get the idea in how to look at it.
The one thing I'd really watch is your calorie level. If you're really carrying the muscle mass I think you are, I think you are starting out a little bit low at 1720. Especially if you find you're stalling early on and having energy issues. I know you've just gone back to work, some other stressors too and tough to say if it's all diet related. There is always some diet pain and low energy that comes with prep but it's quite a ways out to be feeling it already. The danger is you will have to lower calories further, energy levels continue to drop and you'll still have several weeks left and not a lot of room to move when you stall out.
There's a couple different thoughts on that. You can bump up the overall calories a couple hundred and take advantage of the time. You could structure at least 50% of your carb intake to fall around your lifting sessions, both before and after. That will help with energy there. The other thought is the structured refeed. Different than a cheat but a planned and measured increase in carbs once a week/ twice a week...timing again relates to bf and timelines. Some people do that over one meal, while others will do it over a day but find that it will keep things moving and helps with the energy levels too. I can give you more info on how to set those up too if you go that route.
Just a few thoughts to mull around for ya!!
I think you're in a decent position though and have the time to keep the diet reasonable vs that intense drastic cut. So keep working hard!! You're doing great!
But... When I look in the mirror, I can see changes. My abs are starting to appear!!! And my arms were looking great at the gym yesterday. Legs aren't there yet. Not even close. But I know that's how it works for women--legs are always last. And I've been having my husband take weekly pics and those show some signs of progress. But that damn scale doesn't show shit!!! I get so mad!!! 
