I do not understand why team managers did not set an exact date for starting SALE 1 stage. I do not see or posible dont understand, if there is no exact reason for which there is a deadline in the smart contract on January 20, and SALE 1 does not have the start date. Without understanding the logic of such a setting, I can think of anything about their ability to manage such a project.
If in the smart contract there is a deadline of January 20, I think setting the token distribution period in ICO must be set as the time period, so that it is possible to raise the necessary funds. If pre-sale sells only 2,500,000 tokens at the best price, then you can sell 13,500,000 by January 20 at a higher price, it must begin immediately after the pre-sales period. It is unlikely that you sell 13,500,000 tokens in an undetermined start-up period, but after December 27 in the context in which smart-contract January 20 is the deadline. Otherwise I appreciate the idea of the project and sincerely I wish very successful.
I admit honestly, I do not understand the problem you described. I will try to explain it, as I understood. I apologize if my answer is not satisfactory for you.
PRE-SALE is part of ICO. It will last from 20 to 27 December. It is likely that it will last shorter. If we sell 2,500,000 tokens - the pre-sale will end. The ICO runs from December 27 (then we start selling SALE I).
All dates are specified

If you have any questions, I am at your disposal.