Hi!
I recently had to look for a long time to find this thing, after i encountered an issue with my pcb prototype design. I unfortunately placed an ic over the isp pogo pin interface and had to find a workaround without having to immediately create a new revision.
https://hobbyking.com/en_us/atmel-atmeg … tore=en_us
Take a look, mabe something like this could be of use for others.
Best,
Andre