Adding a newline above PS1 that survives prepending

In OBSD ksh, I had a PS1 which prepended a blank line:

PS1="\n[\u@\h] \w\n\$"

The problem with this was that pyenv prepends the name of a virtual environment when that environment is activated. Here is the relevant bit of the pyenv activation script:

PS1="(porcupine) ${PS1:-}"

This eats the blank line, turning

[myusername@myhostname] ~/some/path $ echo foo
foo

[myusername@myhostname] ~/some/path $

into

(virtual-environment-name)
[myusername@myhostname] ~/some/path $ echo foo
foo
(virtual-environment-name)
[myusername@myhostname] ~/some/path $

This is annoying, so I tried to fix it with tput:

PS1_TEXT="[\u@\h] \w\n\$ "
PS1="$(tput sc il1 nw)$(tput rc DO 1)\n$PS1_TEXT"

This moves the cursor to the row above the virtual environment name, makes it a blank line, then returns and sticks in my original PS1. This almost works, but when I hit the bottom of the terminal window, the virtual environment name vanishes. This is annoying, again.