What is the difference between a change/cancellation fee and a reissue fee?

Does a ticket have to be reissued if a flight is changed, but the routing remains the same? What if the date of a segment changes?

For this fare rule for example, there is a waiver of change fees for schedule changes, but there is a reissue fee.

PENALTIES
" CANCELLATIONS

AFTER DEPARTURE
CHARGE USD 240.00 FOR CANCEL/NO-SHOW/REFUND.
WAIVED FOR SCHEDULE CHANGE.
NOTE - TEXT BELOW NOT VALIDATED FOR AUTOPRICING.
--
PENALTY WILL NOT APPLY TO INFANT WITHOUT A SEAT/
APPLY CAT 19 PROVISIONS FOR INFANT WITH A
SEAT // CHILD
--
CALCULATE DIFFERENCE BETWEEN FARE PAID AND
QUALIFYING FARE FOR TRAVEL COMPLETE
USING FARES OF ORIGINAL TICKET DATE /
LESS CANCEL PENALTY /
REFUND RESIDUAL VALUE IF ANY TO ORIGINAL
FORM OF PAYMENT.

CHANGES

CHANGES PERMITTED.
NOTE - TEXT BELOW NOT VALIDATED FOR AUTOPRICING.
--
CHANGE MADE TO OTHER THAN THE FIRST TICKETED
FLIGHT COUPON -
--
THE FARE LEVELS IN EFFECT AT THE TIME OF
ORIGINAL TICKET ISSUE WILL APPLY - ALL
PROVISIONS OF ORIGINAL TICKETED FARE APPLY.
--
IF THE NEW ITINERARY QUALIFIES FOR THE
ORIGINAL TICKETED BOOKING CODE FARE -
BUT RESULTS IN A HIGHER FARE -
DUE TO DAY OF WEEK TRAVEL / SEASONALITY /
CHANGE TO FARE BREAK POINT -
COLLECT DIFFERENCE IN FARE.
//OR//
RESULTS IN A LOWER FARE - DUE TO DAY OF WEEK
TRAVEL / SEASONALITY / CHANGE TO FARE BREAK
POINT -
REFUND DIFFERENCE IN FARE TO ORIGINAL FORM OF
PAYMENT AT THE TIME OF REISSUE.
...

and then:

VOLUNTARY CHANGES
IN THE EVENT OF CHANGES TO TICKETED FLIGHTS
BEFORE DEPARTURE OF JOURNEY AND WITHIN TICKET VALIDITY
CERTAIN DOMESTIC REISSUE PROVISIONS MAY BE OVERRIDDEN
BY THOSE OF UA INTERNATIONAL FARES
CHARGE USD 240.00 FOR REISSUE OR HIGHEST FEE OF ALL
CHANGED FARE COMPONENTS - CHILD DISCOUNTS APPLY - NO
FEE FOR INFANTS W/O SEAT AND
REPRICE USING CURRENT FARES - ONLY BOOKING CODE
CHANGES PERMITTED
PROVIDED ALL OF THE FOLLOWING CONDITIONS ARE MET-
1. NO CHANGE TO FARE BREAKS
2. WHEN NO INTL COUPONS REMAIN - ALL NEW TRAVEL
MUST BE DOMESTIC
3. CHANGE IS ON/BEFORE DAY OF ORIGINAL SCHEDULED
FLIGHT
4. UA FARES ARE USED