Laying before the House of Lords is the formal registration of an instrument. Some instruments are laid before both Houses, some, to do with financial/tax matters, are laid before the House of Commons only.
All treaties and PNSIs require this step but not all Statutory Instruments. For items laid in recess the date laid will be the date laid and not the date of the Lords Business. Links to the LBP to be added retrospectively when the LBP is published on the return of the House