Sure but you obviously don’t need to pick something called Christmas savings to be saving specifically for Christmas.
Plenty of fixed 1yr products to pick like the First Direct where you could potentially get about £50 depending on deposit.
It’s like those Park Christmas savings which just hide the temptation to spend it. They have a purpose for some people.
You can definitely be investing for a year. There’s no specific timescale, just the longer it’s in the more bumps are ironed out. Could it beat £12.19 putting £125 in each month for just a year, I would say it’s a strong yes with blue chip stocks or ETFs like IITU. But not guaranteed so not good for everyone where it could be -£12.19 return or worse.
I’m surprised Principality are opening products whilst most are shutting them down.