Is purchasing an Umrah ticket at a lower price long before the travel date, while its price increases as the date approaches, considered forbidden usury (riba)?

What the questioner mentioned is not a sale, but rather a lease, and it has no relation to usury (riba). Even if it were a sale, it is permissible to sell a commodity for a higher price when paid in installments than when paid immediately; this is because time has a share in the price, and Islamic law has not specified a particular percentage for profit.