A person on whom a notice has been served under section 352, . . . or 372 (notices requiring the execution of works) who wilfully fails to comply with the notice commits a summary offence and is liable on conviciton to a fine not exceeding level 5 on the standard scale.
The obligation to execute the works specified in the notice continues notwithstanding the expiry of the period which under section 375(2) is appropriate for completion of the works in question; and a person who wilfully fails to comply with that obligation, after being convicted of an offence in relation to the notice under subsection (1) or this subsection, commits a further summary offence and is liable on conviction to a fine not exceeding level 5 on the standard scale.
References in this section to compliance with a notice . . . shall be construed in accordance with section 375(2).
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The provisions of this section are without prejudice to the exercise by the local housing authority of their power under section 375 to carry out the works themselves.