Should an amended 990-T return be made available for public inspection?

Yes. Under section 6104(d), a section 501(c)(3) organization that files an amended 990-T return must make the return available for public inspection either three years from the filing date or three years from the original deadline of the return, whichever is later.

You could amend your 990 series forms with us even if you filed your original returns with another provider.