11.—(1) Subject to subsection (3) of this section, the F11[Minister or the Commissioner may substitute for the description of a firearm in a firearm certificate granted by him or her] the description of another firearm and, upon such substitution, the certificate shall have effect in relation to that other firearm and shall not have effect in relation to the first-mentioned firearm.

(2) Subject to subsection (3) of this section, the Superintendent of any district or any member of the Garda Síochána in any district duly authorised to do so by the Superintendent of that district may substitute for the description of a firearm F12[(other than a restricted firearm)] in a firearm certificate held by a person residing in that district the description of another F12[such] firearm and, upon such substitution, the certificate shall have effect in relation to that other firearm and shall not have effect in relation to the first-mentioned firearm.

(3) A substitution under this section in a firearm certificate shall not be effected unless the rate of excise duty chargeable in respect of a renewal of the certificate after the substitution does not exceed the rate chargeable immediately before such substitution.