Hi Symon,
I have not worked on this scenario, to be honest, however, you can manually copy the kernel in (DIR_INSTALL)\exe\uc\<platform> after the SP update.
SAPHOSTAGENT, can be update in minutes.
Refer, https://help.sap.com/saphelp_nw73ehp1/helpdata/en/39/a1f623bae74a2784f88282c8652070/content.htm
Divyanshu
