Substantive changes should be assessed and are ordinarily addressed at the next application, and some are notified sooner on advice. A change in ownership, a merger or a fundamental change in the enterprise's structure or nature is the kind that matters. Continuing without addressing it leaves the approval describing a business that no longer exists.
The enterprise is assessed as it is, not as it was
The conditions of this classification attach to a business, and businesses move. Where the change is substantive, the position needs to be reassessed: a merger, an acquisition, a sale of a substantial ownership interest, a change in the fundamental nature of the enterprise, or a restructuring that alters who owns and controls it. A relocation of premises is not automatically substantive, but one that changes the equipment, the customer base and the economics of the operation deserves the same scrutiny.
Two practical habits help. First, document changes as they happen, with the lease, the equipment list, the reason for the move and the effect on revenue, so that the next application is supported by a contemporaneous record. Second, ask counsel at the time rather than at renewal, because some changes can be addressed cheaply when recent and become a defect only through being left.
The one approach that reliably causes difficulty is treating issuance as the end of the process.