Update network

Hi all,

I am currently updating my network site which has about 450 users and is still expanding. By browsing the forum, I’ve come to know that after updating the main site, the sub site will be upgraded once the user logged into their own site. The process of upgrading each sub site automatically can be done by clicking on the Update Network button but to upgrade the sub site, it takes a long time to complete so I am thinking to skip the Update Network process and leave it to user to trigger it when they log in.

I noticed that my users are not actively log into their site and thus I am wondering, if let say I upgraded to 3.5.1 and after that upgrade again to newer version without updating those sub sites which are still lower version than 3.5.1, will it break the multisite.

At the same time, I am also looking for guidance on how to speed up the Update Network process. Currently I notice it only update 5 sites at a time.

Before I end, I thank you for your time for reading my post.