As soon as + present perfect or present simple

[barnej0096]

'As soon as I...... (have) a look at the designs, I...... (send) them to you. You'll get them by Friday.' In the second gap I know that I should use 'will send' but I don't know why the answer in the first one is 'have had'. Is it incorrect to say 'have'?

[Chicken Sandwich]

NOT A TEACHER

If I understand the information presented in English Grammar in Use correctly, it is often possible to use either the present simple or the present perfect after when, after, until and as soon as.

From English Grammar in Use, p. 50:

It is often possible to use either the present simple or present perfect:

I'll come as soon as I finish. or I'll come as soon as I've finished.
You'll feel better after you have something to eat. or You'll feel better after you've had something to eat.

In your sentence, both "have" and "have had" are possible in my opinion.