plz clarify if u have applied for interview through proper channel or not ( i.e by getting departmental permission certificate from education dept) .
if yes, than no need to resign u may get lien for 2 years ( it is extendable for 1 year) from education dept. in this way ur lecturership will be retaind ( than automaticaly expires )
if not, than simple regination ( while showing ur reasion ) will be required.

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to understand wisdom one must have wisdom, muzik is nothng if audience are deaf