Rolling admission	Round admission
Meaning	Universities keep accepting applications until all programme seats are filled	Universities accept applications by several phases
Period	Usually 6 months or longer	Usually 3-4 rounds with specific deadlines 1st round: Aug-Oct 2nd round: Oct-Jan 3rd round: Feb-Apr
Application result	Available within 4-8 weeks	Available after next round begins

Rolling admissions	Pro	Con
	The sooner you submit application, the more chances of getting accepted	You have less time to prepare for application if you wish to apply early

Round admissions	Pros	Cons
1st Round	Early application reflects that you are serious and well prepared for further study The selection committee is not too picky at this round, so you may have a higher chance of being invited for interview In the first round, the numbers of slots available is more and the opportunity to be placed stands a higher chance in the wait list.	If you have an average academic performance, you may have to wait until further rounds as the selection committee wants to see the quality of forthcoming applications in the next rounds You may not have sufficient time to retake the graduate admission tests/ English proficiency tests if your test results are not satisfactory
2nd Round	You have more time to polish your application portfolio before submission	It is the most competitive admission round as majority of applicants submit application in this time
3rd Round	No significant advantages	Many seats are already filled up and your chance of getting accepted is relatively low

Advice to your further study preparation: Start early and allow plenty of time to prepare for the admission documents and tests.

Reference: https://www.mim-essay.com/blog/ideal-round-apply/