Benchmarking Run & Software Feedback

Hi All,

I signed up for a 5km plan and went outside to do my run, the first notification popped up to do the training run and I wasn't ready to run.
Went back outside after sorting a few things and the benchmark run didn't pop up as the suggest exercise.

So on my 255 Music I went Start > Run > three dots (Up) > Training > Benchmark Run and then did the 9 minute benchmark run.

Immediately after the run, nothing changed in my plan and I though "ahh it'll take Garmin some time to see the run and adjust the rest of the plan" 
Two days later (Today) my planned activity is a benchmark run?

1. Reading a lot of reddit and here, it seems selecting the benchmarking training run like I did won't actually count towards the 5k plan?
What kind of *** software coding is that?

2. Why can I not point in the app the 5km plan to a benchmarking run?
If I've done the benchmarking run, why can't I just go point it to the benchmarking activity?
I would think that if a benchmarking run was completed within the week/month you should be able to say "Hey here is the benchmark, not much has changed, use this"

3. It seems like this is a very common issue from what I can read online. I tried all the sync fixes, change it to training, create a new plan and so forth and nothing works.
It seems like no real fixes exists besides running the benchmarking again, what happens if I do a proper session and then that isn't recorded?
The first experience has been quite bitter and doesn't give me much faith the rest of your plan experience will be any better.

People seem to have been hoping for a fix for quite a few years now, so just adding my frustrations on the forums to try drive change and improvement.
Thanks