Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Bengaluru to Quito as you normally would.
KLM is one of the carriers that may have flexible change policies. You can use our site to filter for other airlines that may also have this kind of flexibility.
This is defined as Bengaluru Intl Airport (BLR) and Quito Mariscal Sucr Airport (UIO). Codes like Quito Mariscal Sucr Airport are often used to just call airports uniquely.