Right. "Reissue," as used in this context, is a generic term that includes revalidation as well. Changing the dates of a flight, without changing the routing, does not require the ticket to be reissued -- merely revalidated -- but does incur a change fee. Except for the amount, which makes me think that this fare is for a foreign market, since change fees are set by competitive pressure on a market-by-market basis, this is essentially boilerplate text.

As Kacee notes, the "schedule change" clause refers to a change on UA's part, not the customer's. If UA changes the flight schedule dramatically, that clause waives the fee for changing the itinerary and reissuing/revalidating the ticket.