When we received your notice of expansion, we at (name of firm) were overjoyed.
There are very few firms that can boast of the success you have achieved over such a relatively short period of time. A great deal of that success, in our opinion, must be directly attributed to your strong leadership and the sense of direction that you provide. This is all the result of hard-work put in by you for such a long time.Please accept our heartiest congratulations and best wishes
for your continued success.