We have all been there... invasion failed with 90%
nothing to do about it, just bad luck.
Sometimes it happens 2-3 days in a row and every time you have to wait 24Hrs. So most likely when you find a good planet, your bane won't upgrade because you failed invasions 2 days in a row. Especially when the owner of the planet is inactive.

my suggestion:
if you fail, your timer is not 24hrs but reduced with the succes rate

example: if you fail with 90%, your invasion timer is reduced with 90% or your timer is 10% of 24hrs.
this is 2.4hrs or 2hrs24minutes
if you fail at 50% then your next invasion timer is 12hrs
if you fail at 10% your next invasion timer is 21hrs36

Against active players we could suggest keeping the 24hr rule but against inactive players we should reduce the timer if invasion failed.

For the Bane Ally, after the 48 hr window, just 1) alert the planet to your legion, 2) purge the planet from your database, 3) reload your planet tab to find the planet you just alerted, 4) invade the planet.

Works with any planet to level the ally. Just don't forget to do #1 first! Quite a few have accidentally purged a nice planet :p

That has nothing to do wit what he said...

However, I'll still -1 the suggestion. The timer is there for a reason. I see no point in changing it.

It did have to do with what he said as it was the reason for the suggestion in the first place. Please read the full post next time.

And my comment will help him to level his bane ally in the event this suggestion doesn't get implemented.

no the comment will help him circumvent the games intentions of you ACTUALLY DOING A SCAN RUN or having a planet alerted.

if you fail your planet invasion, you can always use a paradox generator to reset your invasion timer.