With regular draws
Abhishek - Why do you think CIC won't meet 75000 quota with 2750 every 2 weeks?
I assume the quota which you are talking about is the PR quota through the FSW + FST + CEC programs. Please note Express Entry also includes certain PNP programs too.
Also, 1 ITA does not always equal to 1 PR due to the below mentioned reasons:
1) ITA can be declined
2) ITA would expire if applicant does not submit application within 90 days
3) If applicant applies after ITA, the application can be cancelled or rejected
4) 1 ITA can include 2 PR's (Primary applicant + spouse)
CIC issued over 85,000 ITAs in 2017. Let's assume the ITA counts for 2018 would be same as 2017 even though the overall PR target is slightly higher this year. This means 85000 ITAs to be issued in 2018. If there are 26 draws (only bi-weekly draws), they would need to issue around 85,000/26 = approx 3250 ITAs per draw OR they need to have around 31 draws with 2750 ITAs which will lead to some 1-week gap draws.
All this is assuming the ITAs issued in 2018 will atleast be same as that issued in 2017.