withdrawing from match


dear prab,
i have been offered a prematch by a program( i donot wish to reveal the identity of the program now). i signed the "letter of intent" but i have not signed the official contract yet. here are my concerns..
1. can i withdraw from nrmp now or should i wait till i sign the contract?
2. is there any way programs can find out if i have withdrawn from the match?
3. what do i show as reason for withdrawl in nrmp? there are 2 options. 1)non-nrmp position, 2) applicant's request. which box do i check to withdraw? ps: prab,your advices and guidance through this entire journey of my usmle to match was invaluable. u r a life saver. proud of u!!! thanks a million!!!

Hi, Congratulations on the

Hi,
Congratulations on the prematch. It is a wonderful feeling to finally get over this. 1. You have plenty of time to withdraw, so no rush, just wait until you sign a contract. 2. If you withdraw from the match, the programs will know when they are trying to rank you in Feb but not before that. 3. Applicants request is what you should choose. I appreciate your compliments. Glad to be of some help. Please feel free to help others the same way you were helped. You are welcome to answer questions of other users here and if you wish, we can make you a moderator. All the best. What a relief!
--
You can do it, we can help!
Prab, Moderator

Thank u so much prab! i was

Thank u so much prab!
i was under the impression that programs would get some sort of notification the same day when a candidate withdraws from the match. so i need not rush in. i got 2 other interviews which i cancelled. do u think its safe to cancel interviews before signing the contract? i would be glad to help others like u do here. although im not well informed about the whole process like you are, i shall try to answer questions which falls within the limited domain of my knowledge :)