Samsung s-planner as interface to google calendar, miss 3-day layout S-planner app lost 3-days layout after last update.

That made me cry.

I want to solve it with anyway, change calendar app, or rollback to old s-planner version, or something else?

Please point me to any solution.
If you have saved the previous version's .apk, you can re-instate it. That's why I have AppMonster Pro Backup Restore installed and running: it captures each and every .apk installed, so I can always revert to a previous version.

If you don't have the old .apk available, and you are talking about a free app, you can check Android Drawer for a previous version's .apk. Download it, make sure you have unknown-sources enabled in your settings, and launch the .apk e.g. from a file explorer. This should install the (old version of the) app without you losing any data.