Thank you very much, zen135.

I hope you receive your acknowledgement and biometric letters soon, hussainkothari. zen135, you mentioned that if the biometrics letter are issued, then one can safely assume that one's payment has cleared and application is 'valid'. For my peace of mind, could you please let me know whether this is...

Dear Moderators and members

I would be grateful if you could let me know whether it is possible that a Tier 1 extension application can be returned as invalid due to failure in collecting payment after the applicant has received a biometric letter.

Thank you for your help.