A donor forward types as A but does not have Anti-B. Do you discard?

It would surely depend on several factors.

Firstly, have adsorption and elution studies been performed with anti-B to ensure that the donor is not actually an A(B weak)?

Have studies been done with enzyme-treated group B red cells against the donors plasma at varying temperatures to ensure that there really is no anti-B present?

Has the apparently healthy donor been checked for any "silent" underlying pathology, such as hypogammaglobulinaemia? Or, indeed, has the donor been given a SC or BMT in the past and is mistakenly altruistic in trying to give blood to others, now that they are cured of their own life-threatening disease?

I wouldn't discard immediately, but I would be extremely wary.

If you can't get the reverse type to come up within the limitations of the reverse cells manufacturers directions, then I think you would have to discard the donation, as a valid ABO cannot be obtained. Just thinking from a regulatory standpoint...

we do not use the unit for transfusion but perform elution studies and workout group