The FCA have granted a six month adjustment period to UK banks to implement an aspect of the open banking regulations that effects the bank feed integration with Xero.
Barclays bank feeds and all feeds connected through Yodlee would have been affected. Different banks and feed providers will have different implementation dates, but those who have not already moved their bank feeds to the new system will have longer to put this in to place. Xero will provide you with notifications when you log in once your new feeds are available.
Read more on Xero's blog here.