lidity of a permit may be further restricted in the following conditions: 1. In the case that a building or structure has been ordered repaired or demolished in accordance with Los Angeles Municipal Code Sections 91.8903, 91.8904, or 91.8905, such time limits as are specified therein shall apply. 2. The Department or the Board may, because of unusual circumstances or conditions such as, but not limited to, the demolition of an imminently hazardous building, or a grading operation which may be subject to flooding during the rainy season, impose restrictions upon the time limits for expiration of any permit. 3. The time limit for the validity of relocation permits shall be as specified in LAMC Section 91.8306. 4. The time limit for the validity of tent permits shall be as specified in LAMC Subsection 91.106.1.3. 5. The time limit for the validity of permits for the installation of metal bars, grills, grates, security roll-down shutters, and similar devices, and of quick-release systems shall be as specified in Los Angeles Municipal Code Subsection 91.107.4.5. 6. The time limit of validity of permits for temporary signs on temporary construction walls, or for temporary signs on a fence of solid wood or similar material surrounding a vacant lot, issued pursuant to the provisions of Section 14.4.17, shall be as specified in Subsection 14.4.17 C. of the Los Angeles Municipal Code. (b) Permits which have expired shall have the site, building or project restored to the condition which existed immediately prior to the commencement of work described by such permit. (c) It shall be unlawful for any owner, either before or after the issuance of a permit under this section, and notwithstanding the issuance of such permit, to fail to comply with any order, determination or action of the Department or Board.