Hello,
I'm experienced project manager, so I completely understand meaning of project milestones and deadlines.
Exact bid have relatively low cost and long duration. The reason is as follows:
-1st (reg. duration) - I don't see exact amount of work, so duration is taken with reasonable reserve
-2nd (reg. pricing) - I've registered today, so I have no other opportunities to get orders than to lower price.
Please let me know, in case you have any questions.
Have a nice day!
Eugene