SBI Securities and long names

Anyone with a long name managed to register the whole name with SBI Securities? I don't have a middle name, it's just that they trimmed my first name when I registered because of the total number of characters. I called their support and they suggested to apply for a name change from a link hidden somewhere in the "forgot my password" page to fix this. I did that and they were generous enough to add 2 additional letters from the initial registration and trimmed the rest.

The result is that my mortgage with Shinsei bank is 0.68% instead of 0.59% because I couldn't link the accounts and get the discounted rate. Shinsei bank when we finalized the details told me to let them know when I link the accounts. I assume they can adjust my rate after 6 months. But I still don't know if I can ever get SBI Securities to register my full name.

by muku_