I would have thought that many restaurants offering a degustation are likely to stagger dining times. Whilst I’ve never done one in Spain, I’ve eaten in a number of high end places and easily been able to get tables at around 8pm. You tend to find your fellow diners are also non-Spaniards, with the locals booking tables for what they regard as a more civilised, later time.
If that’s not available, then I would have thought lunch would be the way to go
