The first number is the real replacement in all the units, and the number in brackets is what you set to the unit.
If you set an Army to 75%(75%), then a Corp under it can be set to 75%(PRO), and a division under the Corp can be set to 100%(PRO) or 100%(100%) like normal.
I've tried just now.
In round 1, i've checked the autoreinforcementlog.txt under logs directory, all the replacement are in priority cycle 2.
And i set as this, all the units are requesting infantry, except OKH, 11A, 6A.
In round 2, i check the autoreinforcementlog.txt, and found that in priority cycle 1, only 6 times infantry to 79th Division, the other replacement are still in priority cycle 2.
46th and 170th are only one infantry, and the other infantry are randomly transferred to the units i have not touched, but none is transferred to a HQ. The units under LIV Corp and XXX are get nothing, except for 170th.
And i must correct what i've said in last post. A 100% unit may also return troops.
I found 2A(HUN) and 8A(ITA) both return 1 staff from their 10 staff to OKH in each round, and IV Corp(HUN) and CSIR(ITA) both receive 1 staff in round 2, their staffs are increase from 8 to 9(the IV Corp(HUN) have received another HQ from Highcommand, so it's now 10 staffs).
It seems that the HQ with only other HQs under it will return it staff to OKH for the HQs that command troops.
And as you see in my set list, i cannot set 46th to PRIO/PRIO, i think PRIO can only affect one level in HQ chain.