Some explanation on the TWRP Reboot menu

Boot TWRP in slot a; Install LineageOS , TWRP will install it to slot b! Flash to slot b

I'm working with Android 9 Pie and I have one slot rooted and the other is not My reasoning to have my phone this way is

rabbit slot pg Dynamic Partition Super Partiton AB Slots TWRP

low profile slot drain Thread AB slot issue, TWRP only on one unrooted rom on other Can't mount from TWRP TWRP is on slot B but not slot A I can only reboot to system from TWRP