possible to lose 30lbs a month?

Possible?.......sure, anything's possible.
Is it healthy and/or safe for you to lose that much in that short period of time?.......absolutely not, and don't listen to any others who would tell you differently.

Cut off a limb, done!

Yes, but you won't maintain it. Slow and steady wins this race. 1 pound a week is the way to go if you want to stay slim and healthy for a life time.

Here you go...... UFC professional fighters can lose up to 30 lbs in 5 days!

Dont fancy it myself though. There is no "quick fix" for losing weight and getting in shape, its a life change and the slower and more natural the better!

If you manage a natural 2 lbs per week loss, then by your friends wedding you will 8-10 lbs lighter! Not half bad..........

Good luck!

Well if you are only eating 1200 cal on days with 40-60 minutes of kick boxing you are eating too few calories. At 254lbs this is a huge deficit. As others have said it is considered the safe max to lose 2lbs a week, I also like to note that if you are decently fit already this is probably too much.

What is your TDEE?

This isn't a complete golden standard though. A lot of peoples bodies respond very quickly to healthy nutrition changes and becoming more active. It is not uncommon for the weight to just start falling off in the beginning. 30lbs in a month for a women? Probably not. I've seen guys do it though and gain strength and fitness in the process.

In extreme cases, like MMA fighters like ilovemilkymoo suggested, there are ways to lessen the LBM losses on a crash diet. Although if you are out of shape and over weight I strongly would suggest not going this route. A competitive athlete knows how their body responds to these things and has the muscle mass and metabolism to burn fat at an extremely accelerated pace in a huge deficit. These people are usually under the supervision of coaches or health professionals, and do everything they can to mitigate the damages. Also, many obese people are on the verge of having major health issues if they don't have them already.

If you still have your heart set on running a risky diet, then read this book. I'm only posting this because I believe a lot of people are head strong and will go against good advise in a futile effort to lose weight immediately. Again I do not recommend doing this, but if you are this will give you the guide lines to minimize risk.

http://www.files.failedmiserably.com/data/aironz/The%20Rapid%20Fat%20Loss%20Handbook.pdf

Thank me later for saving you $30 for the read.

If you were on the Biggest Loser and could work out all day every day and constantly had personal trainers and nutritionists around you....sure....maybe for the first month.

Otherwise, whatever you do to lose that much weight that fast won't be healthy and unless you keep doing it forever, the weight will come back. Have patience. Focus on 2 lbs/week.

Also keep in mind that the more weight you lose, the more you'll have to pay for alterations. They generally don't recommend losing weight during the last few weeks because you've had your final fitting. You don't want the dress to sag. A dress that fits well on a 250-pound frame looks MUCH better than a dress sagging on a 220-pound frame.