I am using RBS credit card for quite a few years and I pay my bills much prior to the due date as a practice. I usually drop the cheque at Phase 3B2 Mohali SkyPakBox. I received a bill of Rs. 8566/- on 3rd Dec 2010 statement and dropped a cheque of Rs. 8566/- on 20th Dec 2010, due date being 23rd Dec 2010. The cheque was probably lost in the interim and the amount did not reach RBS. I realised it when I received the next statement on 3rd Jan 2011.
I paid the bill of 8580/- the same day while the rest of my bill (about 10500) was paid before 23rd Jan 2011 the normal due date of my bills but RBS accrued a late fee (Rs650), finance charges (Rs551) and a service charge (Rs123) in 3rd Jan 2011 statement and again Rs350+ in 3rd Feb 2011 statement. I wrote to them on 3rd Jan and later on two other instances but did not get any reply from them till the last statement was received by me. Despite my requests and no error of mine, they have not moved an inch.
I remember a similar problem I faced with CitiBank card but they had reversed the charges.I strongly recommend if you have other cards do not use RBS card.