According to the Fedora 28 schedule [1] we are going to reach the "Software String Freeze" deadline in one week on 2018-Feb-27. Beyond this deadline there should not be any changes in strings, ideally.
If you want to help with translations then, please check the packages that follow Fedora release cycle (Main projects): https://fedora.zanata.org/version-group/view/main
The time limit for the translations is according to the schedule [1] planned on 2018-Mar-06 (Software Translation Deadline).
[1] https://fedorapeople.org/groups/schedule/f-28/f-28-trans-tasks.html
Thanks for all translated strings and Regards, Jan