OS X El Capitan 10.11.4 Combo Update is available for download at Apple Support
I download the Combo Updater in preference to activating Software Update as the combo will iron out any problems from previous versions. An old habit which night just still be valid. No longer tedious backup first as all my documents are in Dropbox on an SSD. Everything else is taken care of with a backup protocol.
Don’t you miss the cat names?