We recommend that you add the sub-allocation via the myafrinic portal.
You may do this via https://my.afrinic.net as follows:
o Log into https://my.afrinic.net
o Go to Resources -> IPv4 Resources
o Click on "+" to expand on the target allocation
o Click "Add Sub-Allocation"
o Fill in the form and submit
The AFRINIC hostmasters will then revert back to you for evaluation of the request.