Here I am again, the weather is just fine
From Mindelo to Vairão or Vilarinho is not a waymarked trail but fairly straight on.
But you still are in the industrial infra structure north of Porto.
If you want to change from the coastal to the central route you better could go on to Vila do Conde and follow the aquaduct route in stead of the (partly) river walk to São Pedro de Rates.
or you change at Caminha and follow the waymarked ecopista path along the Minho river to Valença do Minho.
There was a topic about the aquaduct stage here on the forum the other day .
Other alternative is to take the metro from Porto to Fórum Maia or Vilar do Pinheiro and start from there walking to Vairão and Vilarinho to São Pedro and on.
if you walk on the Central, don’t miss albergue
Casa da Fernanda in Vitorino de Piães between Barcelos and Ponte de Lima. The only albergue on the caminho Português that provides a similar sphere as albergues on the CF with common dinners and breakfasts .
Bom caminho