Champion Airlines
To upgrade to business class with Singapore Airlines, explore options like using KrisFlyer miles through the airline's loyalty program or consider cash upgrades at check-in if available. Frequent flyers can log in to their KrisFlyer accounts online to check for upgrade possibilities. Additionally, some airlines, including Singapore Airlines, may offer the chance to bid for an upgrade, where passengers can place monetary bids for a higher class seat, subject to availability. Keep in mind that specific policies and options may vary, so it's advisable to check with the airline directly for the most accurate and up-to-date information on upgrading to business class.
https://championairlines.com/blog/singapore-airlines-business-class/