Noel-
Sometimes an inadvertent push turns the key...and you just did that! My 116 bar tune took 57 seconds to load 20 choruses on my 2018 setup. So thinking it's time to actually put 2019 on my main PC (test PC has it), I went to the PG site to see if the upgrade might help. Lo and behold, the realtracks speed generation section revealed
"Band-in-a-Box® 2010 and higher have an option to 'freeze' some or all of your tracks. This means that the next time you load your song and play it, it will generate and play almost instantly."

I never used track freezing for fast generation...since I'm mostly dealing with one single looped chorus....but Bingo...it worked like a champ....problem solved......you're the hero of the day.
Thanks a million for taking the time to help out.