The licenses come in 1, 3, 5, 7 or 10-year terms. You should simply purchase the 3-year license, because each 3-year license is the same exact cost as if you bought a 1-year license twice. What I mean is, the longer the license term you purchase, the more discount is automatically factored in. So if a 1-year AP license list price is $150, then the 3-year license is not triple that, it's actually double that, so $300 for 3 years, which would cost the same as if you purchased 2x1-year licenses. When logged into your Meraki Dashboard, click into the search window and type "license calculator" and you can input your existing license info and try out different renewal options to see you new co-term date.
Also, the answer to the original question is no. If you bought 4x1-year licenses, you would be licensed for 4 APs for 1 year. That cannot be "rebalanced" over 2 APs for 2 years.