Having made an appeal an appellant may subsequently state that
he wishes to withdraw it. If you have no objections settle the
appeal in the same way as any other appeal settled by agreement
(see AH0330).
If you are unwilling to allow the withdrawal, e.g. because it
appears that an assessment may be inadequate, you should notify the
appellant within the statutory time limit of 30 days (see AH330)
that you object to the withdrawal of the appeal and proceed to
ascertain the correct amount assessable.