Northern Spain

Lads I’m guna try getting to northern Spain ,rosslare to bilbao,and squeeze it into a week maybe 8 days at Easter so potes hopefully , and maybe borgos ,for inland towns, no further ,but looking ideas for coastal towns with a beach ,on way back to Bilbao with aires ,not fussed on campsites if possible

You might be lucky, but I wouldn't base the trip on going to the beach at that time of year, I walked Camino Frances a couple of times, mid April to mid May and got every weather condition, the one thing I didn't get was Sunburn.
Last time may until end of June was better, but still rain the first two weeks with snow and mist in heigh places. That said it's a lovely area.

Fair enough ,but thinking beach environment with a coat on still might be nice

We've been going to salou the last 3 years at easter as the kids have the 2 wks off school...its about 5 to 6 hrs drive from bilboa to salou by motorway...there is a pricey toll on this road though, I think its about €30..we tried the non toll route last year and it was up over a mountain so we just do the motorway now for the handyness and to save time...we have it booked again for 2025...the weather is usually high teens or early 20's...this year easter was early so the first week the weather wasn't great but the second wk was good...easter is mid April next year so I'd say the temp should be early 20's all going well....the outside pools on the campsites can still be cold though if they are not heated but there's loads to do in salou....tarragona is a nice place to visit also.