In-press version of the Journal

I am think to create an In-press category for our Journal, We have both print and e-version of our journal

In-press = articles are published online as finished with editorial process but the Issue is not closed yet, no printed version available
Current = a closed current issue, available in printed version
Archive = all passed closed issues

Such as this one

http://www.sciencedirect.com/science/journal/aip/09242716

How can I achieve this please?

Take a look at this thread:

Does this mean that we have to keep make these changes after each OJS upgrades, please?

Yes, a local code change such as this would need to be validated (to confirm if it is still relevant) and reapplied (if still relevant) at each upgrade.

I hope that this will be added as Admin function by selection in OJS 3, these sort of functionality increase the popularity of the system.