Can you try to map it with PCR since you may face few problem if you give maximum entitlement let say employee has reached his maximum balance 30 days but employee has utilized 5 days
2006 appearance 01.01.2014 to 31.12.2014 number 30 deduction 5 = 25 days but system will not generate the quota if existing balance is 30 days as per employees concern he utilized 5 so he can get 5 more days.(Depends on accurals period scenario varies)
Further more this is maximum entitlement case.
As you mentioned carryover should not exceed 30 days i.e when you are carrying forwarded remaining balance to the next year then you wanted check that maximum carry forwarded days accordingly employee years of experience with your organization.
1) you have to query the experience of employee on date when you are carrying forwarded (need exact date when your carrying forward)usually it is end of the year VARSTCURMO or BCURMO VARSTREDAY or BCURDY operations to query month and date.
2) Utilize the Operation next to this FRXXC remaining balance then use operation HRS?30 then if it is greater than pass HRS=30 to time type then later you can utilize the same time type to generate quota either with a PCR or else pass the same time type to base entitlement configuration.
Before this you have to query years of experience check operation HRS=YSAMXX according to requirement go through the same by using PE04 you will get an idea.
These all depends up on organization Quota accural periods and etc.
Regards
Venkatesh