Thank you for your email, for the tender period we will discuss with the Employer but think that an extension is possible.
For the construction period can you please explain why you think that a period of 20 months is needed for a 3 storey single house with no basement with an area of only 1,400m2 , this is double what was included in the tender issue letter of 10 months. If you can explain this with your tender submission it can then be discussed with the Employer but it does seem a very long period for what is a simple house.