Welcome to Flyertalk Paul! I suggest you have a good read of the companion voucher thread, excellent FAQs and lots of tips. Long story short, but you’ve likely missed all the guaranteed seats for that time frame and so will be relying on a further release which is a maybe or maybe not and hard to make plans around especially with a little one. I’d suggest not trying the voucher on this occasion and looking at cash options / alternative destinations?

https://www.flyertalk.com/forum/brit...iscussion.html