This a weak point in Odoo - Calculate ATP - Available to promise.   The only parameter available is Customer Lead time on product.  (At least for V14).

What we could be want is: Calculation that sum up the delivery time for components from BOM + manufacturing time + delivery time.  Available stock at requirement date should be taken into account (no delivery time). Then if requested date  minus total supply time is later than today, then OK. Else calculate todays date + total  supply time = ATP.   This should not be very complex to develop.  

But be aware: If you have several request you might be promising to much.  I have never seen that production capacity is taken into account on any system for requests. It might be if manufacturing is fully occupied during the supply time. It adds a lot of complexity.

After order confirmation and manufacturing planning, capacity in manufacturing is possible to take into account, and calculate a more precise ATP.

Perhaps this can be accomplished by using the purchase order workflow - i.e. "confirming" the RFQ before sending the PO to the vendor.  If the RFQ needs to be adjusted or cancelled, it is just unlocked and sent through the workflow again or cancelled altogether.