Whilst researching Lladro, I was made aware of the relationship of the markings by a US company which specialises in retired Lladro figurines:-
An extract from Lladro.com explains the relationship between the Daisa and NAO marks found on the figurines as follows:-
"DAISA is the name of the Lladro company which holds the intellectual property rights for the figurines"
"NAO is a brand of the Lladro group, whose pieces are distinguished by the simplicity of their forms, lighthearted subject matters and colourful presentations. All the NAO pieces are executed by The City of Porcelain team of sculptors, and are made at the workshops the company has in the town of Xirivella in Valencia (Spain)"
To clarify..."DAISA" appears on both Lladro and NAO. The Lladro range is more extensive and expensive range than NAO.
Any further thoughts or matters of clarification related to how the markings changed related to the date of manufacture would be gratefully received!