SLA for complaint response?

Hi guys
Anyone know what the SLA is for VS to reply to a complaint?
I wrote a letter in mid-December - had an email on 18/1 saying
"Thank you for taking the time to write to us with your feedback.
I've passed your letter to our Executive office and they'll get back to you just as soon as they can.
Thank you for your patience while waiting for our reply."
But have had nothing since (I did email the person a few days ago but heard nothing).
Really not impressed with VS, beginning to think after my recent experiences plus this lack of customer care, whether I ever want to give them any more business in the future..
thanks
Anyone know what the SLA is for VS to reply to a complaint?
I wrote a letter in mid-December - had an email on 18/1 saying
"Thank you for taking the time to write to us with your feedback.
I've passed your letter to our Executive office and they'll get back to you just as soon as they can.
Thank you for your patience while waiting for our reply."
But have had nothing since (I did email the person a few days ago but heard nothing).
Really not impressed with VS, beginning to think after my recent experiences plus this lack of customer care, whether I ever want to give them any more business in the future..
thanks