Interestingly, the Reforma Horaria initiative coincides with the Spanish municipal elections in May, at which pro-independence parties are seen scoring highly in Catalonia.
The region is one of the wealthiest in Spain and considers itself culturally distinct, with inhabitant speaking Catalan as well as Spanish. It is currently designated a "autonomous community" in Spain, granting it a degree of autonomy from the federal Spanish government.
Catalonia's call for independence from the rest of Spain have gained traction recently. The region's separatist president, Artus Mas, held a referendum on the issue last year, in which the majority of Catalans voted for independence; however the vote was judged unconstitutional by the Spanish government.
He now plans to hold a snap election on the issue in September 2015.
Last month, Mas told CNBC at the Mobile World Congress in Barcelona that an independent Catalonia would probably be economically comparable to Austria or to Denmark; both of whose economies he termed "outstanding."
Read MoreIndependent Catalonia would be richer: President
Mas added that if Catalonia were to be independent, "We would have more money and more legal capacity to take decisions and this is what you can do for your economic structure in your country and to help private companies to do better."
Castillo told CNBC that full-blown siestas were actually very rare in Spain, so the Reforma Horaria initiative could be part of the bid for Catalonia's independence.
"I don't know any place in Spain where working timetables include siesta, neither in Catalonia nor in any other region, so this sounds to me more like a political announcement made to reinforce the idea of difference from the rest of Spain, and to boost its image internationally -- which, eventually, will lead to a supporting attitude towards its independence," she said.
Castillo added that siestas were "more a myth that people from other countries have about Spain" and that they were "definitely not common at all in the cities."
Read MoreSpain to split? Snap vote on Catalan independence
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