I suspect you will see 10 rounds of players signed by most teams, just not at slot values.I really felt they should have done ten rounds mostly because players usually within the first ten have a legit chance to make it to the pros.
To me it sounds like a lot of college seniors/older college kids will be able to sign with anyone they want this off season. Most of the high school seniors will go to college if not taken, so honestly next season should make for some really good college ball cause of a lot more influx of talent than before, but i could be wrong there. I would just advise any non drafted high school senior to go to college so they can get drafted since most of the time that will earn them more money than signing with a team.
So the 4th and 5th round will probably see many players signing for under slot rather than take the chance they go undrafted and end up facing $20K or college. Then you will see about 3 rounds (90 players =>3 rounds, 30 teams) signed for the $20k as undrafted free agents by most teams I would suspect. Getting decent talent for $20k is a bargain most teams will not pass up.
But for HS kids, if you are not going in the first couple rounds of the draft, college has always been the best option.