Tours to Andorra in April are slightly cheaper. This is due to the gradual end of the ski season. In some places there is still snow, and the higher it is, the more it is. You can still ski in Grandvalira and Vallnorda, but thaws are becoming more frequent, and the sun rises higher and higher.
Prices for vacations in Andorra in April are quite low. Occur here and sales are due to the decline in interest of tourists. It is not about low season in general, many people come just for shopping, for the sake of rest in Caldea. But there are more opportunities to save money, and if you are not afraid of humidity and rain, come at this time.