This won’t happen to OpenWrt 19.07. You requested the same in this Czech thread: Verze kernelu 4.19 v OpenWrt 18.06 (Turris OS 4.x)? - Turris OS 4.x [CZ] - Turris forum and as well here Turris OS 5 is coming - #11 by anon50890781 - General discussion - Turris forum.
OpenWrt 19.07 uses kernel version 4.14, which is LTS and EoL is scheduled to January 2024. OpenWrt voted if they should have for the next release 4.19 or 5.4 and they agreed to have support of 5.4.