28.—(1) This paragraph applies, and rule 157(3) does not apply, where a charge is allocated for Court Martial trial and is a relevant charge (within the meaning of rule 157) by virtue of an SDA election.
(2) Where the election charge was brought under AA 1955 or AFA 1955, the Director may not, without the written consent of the defendant, substitute under section 125(2)(b) a charge of an offence if, at the time of the election, a charge of that offence would not have been capable of being dealt with summarily (within the meaning of section 76(6)(b) of AA 1955 or AFA 1955, as the case may be).
(3) Where the election charge was brought under NDA 1957, the Director may not, without the written consent of the defendant, substitute under section 125(2)(b) a charge of an offence if, at the time of the election, a charge of that offence would not have been capable of being tried summarily (within the meaning of NDA 1957).